| // Copyright 2019 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package cache |
| |
| import ( |
| "context" |
| "crypto/sha256" |
| "fmt" |
| "go/ast" |
| "go/token" |
| "go/types" |
| "regexp" |
| "runtime" |
| "sort" |
| "strings" |
| "sync" |
| |
| "golang.org/x/mod/module" |
| "golang.org/x/sync/errgroup" |
| "golang.org/x/tools/go/ast/astutil" |
| "golang.org/x/tools/gopls/internal/lsp/filecache" |
| "golang.org/x/tools/gopls/internal/lsp/protocol" |
| "golang.org/x/tools/gopls/internal/lsp/source" |
| "golang.org/x/tools/gopls/internal/lsp/source/methodsets" |
| "golang.org/x/tools/gopls/internal/lsp/source/xrefs" |
| "golang.org/x/tools/gopls/internal/span" |
| "golang.org/x/tools/internal/bug" |
| "golang.org/x/tools/internal/event" |
| "golang.org/x/tools/internal/event/tag" |
| "golang.org/x/tools/internal/gcimporter" |
| "golang.org/x/tools/internal/packagesinternal" |
| "golang.org/x/tools/internal/tokeninternal" |
| "golang.org/x/tools/internal/typeparams" |
| "golang.org/x/tools/internal/typesinternal" |
| ) |
| |
| // Various optimizations that should not affect correctness. |
| const ( |
| preserveImportGraph = true // hold on to the import graph for open packages |
| ) |
| |
| // A typeCheckBatch holds data for a logical type-checking operation, which may |
| // type-check many unrelated packages. |
| // |
| // It shares state such as parsed files and imports, to optimize type-checking |
| // for packages with overlapping dependency graphs. |
| type typeCheckBatch struct { |
| syntaxIndex map[PackageID]int // requested ID -> index in ids |
| pre preTypeCheck |
| post postTypeCheck |
| |
| s *snapshot |
| meta *metadataGraph // captured once at the start of type checking |
| fset *token.FileSet // describes all parsed or imported files |
| cpulimit chan struct{} // concurrency limiter for CPU-bound operations |
| |
| mu sync.Mutex |
| syntaxPackages map[PackageID]*futurePackage // results of processing a requested package; may hold (nil, nil) |
| importPackages map[PackageID]*futurePackage // package results to use for importing |
| } |
| |
| // A futurePackage is a future result of type checking or importing a package, |
| // to be cached in a map. |
| // |
| // The goroutine that creates the futurePackage is responsible for evaluating |
| // its value, and closing the done channel. |
| type futurePackage struct { |
| done chan struct{} |
| v pkgOrErr |
| } |
| |
| type pkgOrErr struct { |
| pkg *types.Package |
| err error |
| } |
| |
| // TypeCheck type-checks the specified packages. |
| // |
| // The resulting packages slice always contains len(ids) entries, though some |
| // of them may be nil if (and only if) the resulting error is non-nil. |
| // |
| // An error is returned if any of the requested packages fail to type-check. |
| // This is different from having type-checking errors: a failure to type-check |
| // indicates context cancellation or otherwise significant failure to perform |
| // the type-checking operation. |
| func (s *snapshot) TypeCheck(ctx context.Context, ids ...PackageID) ([]source.Package, error) { |
| pkgs := make([]source.Package, len(ids)) |
| |
| var ( |
| needIDs []PackageID // ids to type-check |
| indexes []int // original index of requested ids |
| ) |
| |
| // Check for existing active packages. |
| // |
| // Since gopls can't depend on package identity, any instance of the |
| // requested package must be ok to return. |
| // |
| // This is an optimization to avoid redundant type-checking: following |
| // changes to an open package many LSP clients send several successive |
| // requests for package information for the modified package (semantic |
| // tokens, code lens, inlay hints, etc.) |
| for i, id := range ids { |
| if pkg := s.getActivePackage(id); pkg != nil { |
| pkgs[i] = pkg |
| } else { |
| needIDs = append(needIDs, id) |
| indexes = append(indexes, i) |
| } |
| } |
| |
| post := func(i int, pkg *Package) { |
| if alt := s.memoizeActivePackage(pkg.m.ID, pkg); alt != nil && alt != pkg { |
| // pkg is an open package, but we've lost a race and an existing package |
| // has already been memoized. |
| pkg = alt |
| } |
| pkgs[indexes[i]] = pkg |
| } |
| return pkgs, s.forEachPackage(ctx, needIDs, nil, post) |
| } |
| |
| // getImportGraph returns a shared import graph use for this snapshot, or nil. |
| // |
| // This is purely an optimization: holding on to more imports allows trading |
| // memory for CPU and latency. Currently, getImportGraph returns an import |
| // graph containing all packages imported by open packages, since these are |
| // highly likely to be needed when packages change. |
| // |
| // Furthermore, since we memoize active packages, including their imports in |
| // the shared import graph means we don't run the risk of pinning duplicate |
| // copies of common imports, if active packages are computed in separate type |
| // checking batches. |
| func (s *snapshot) getImportGraph(ctx context.Context) *importGraph { |
| if !preserveImportGraph { |
| return nil |
| } |
| s.mu.Lock() |
| |
| // Evaluate the shared import graph for the snapshot. There are three major |
| // codepaths here: |
| // |
| // 1. importGraphDone == nil, importGraph == nil: it is this goroutine's |
| // responsibility to type-check the shared import graph. |
| // 2. importGraphDone == nil, importGraph != nil: it is this goroutine's |
| // responsibility to resolve the import graph, which may result in |
| // type-checking only if the existing importGraph (carried over from the |
| // preceding snapshot) is invalid. |
| // 3. importGraphDone != nil: some other goroutine is doing (1) or (2), wait |
| // for the work to be done. |
| done := s.importGraphDone |
| if done == nil { |
| done = make(chan struct{}) |
| s.importGraphDone = done |
| release := s.Acquire() // must acquire to use the snapshot asynchronously |
| go func() { |
| defer release() |
| importGraph, err := s.resolveImportGraph() // may be nil |
| if err != nil { |
| if ctx.Err() == nil { |
| event.Error(ctx, "computing the shared import graph", err) |
| } |
| importGraph = nil |
| } |
| s.mu.Lock() |
| s.importGraph = importGraph |
| s.mu.Unlock() |
| close(done) |
| }() |
| } |
| s.mu.Unlock() |
| |
| select { |
| case <-done: |
| return s.importGraph |
| case <-ctx.Done(): |
| return nil |
| } |
| } |
| |
| // resolveImportGraph evaluates the shared import graph to use for |
| // type-checking in this snapshot. This may involve re-using the import graph |
| // of the previous snapshot (stored in s.importGraph), or computing a fresh |
| // import graph. |
| // |
| // resolveImportGraph should only be called from getImportGraph. |
| func (s *snapshot) resolveImportGraph() (*importGraph, error) { |
| ctx := s.backgroundCtx |
| ctx, done := event.Start(event.Detach(ctx), "cache.resolveImportGraph") |
| defer done() |
| |
| if err := s.awaitLoaded(ctx); err != nil { |
| return nil, err |
| } |
| |
| s.mu.Lock() |
| meta := s.meta |
| lastImportGraph := s.importGraph |
| s.mu.Unlock() |
| |
| openPackages := make(map[PackageID]bool) |
| for _, fh := range s.overlays() { |
| for _, id := range meta.ids[fh.URI()] { |
| openPackages[id] = true |
| } |
| } |
| |
| // TODO(rfindley): when building package handles becomes more expensive (due |
| // to precise pruning support), we may want to parallelize this loop. |
| deps := make(map[PackageID]source.Hash) |
| for id := range openPackages { |
| m := meta.metadata[id] |
| for _, id := range m.DepsByPkgPath { |
| if _, ok := deps[id]; !ok { |
| ph, err := s.buildPackageHandle(ctx, id) |
| if err != nil { |
| if ctx.Err() != nil { |
| return nil, err |
| } else { |
| continue |
| } |
| } |
| deps[id] = ph.key |
| } |
| } |
| } |
| |
| // Subtlety: we erase the upward cone of open packages from the shared import |
| // graph, to increase reusability. |
| // |
| // This is easiest to understand via an example: suppose A imports B, and B |
| // imports C. Now suppose A and B are open. If we preserve the entire set of |
| // shared deps by open packages, deps will be {B, C}. But this means that any |
| // change to the open package B will invalidate the shared import graph, |
| // meaning we will experience no benefit from sharing when B is edited. |
| // Consider that this will be a common scenario, when A is foo_test and B is |
| // foo. Better to just preserve the shared import C. |
| // |
| // With precise pruning, we may want to truncate this search based on |
| // reachability. |
| // |
| // TODO(rfindley): this logic could use a unit test. |
| volatileDeps := make(map[PackageID]bool) |
| var isVolatile func(PackageID) bool |
| isVolatile = func(id PackageID) (volatile bool) { |
| if v, ok := volatileDeps[id]; ok { |
| return v |
| } |
| defer func() { |
| volatileDeps[id] = volatile |
| }() |
| if openPackages[id] { |
| return true |
| } |
| m := meta.metadata[id] |
| if m != nil { |
| for _, dep := range m.DepsByPkgPath { |
| if isVolatile(dep) { |
| return true |
| } |
| } |
| } |
| return false |
| } |
| for dep := range deps { |
| isVolatile(dep) |
| } |
| for id, volatile := range volatileDeps { |
| if volatile { |
| delete(deps, id) |
| } |
| } |
| |
| // We reuse the last import graph if and only if none of the dependencies |
| // have changed. Doing better would involve analyzing dependencies to find |
| // subgraphs that are still valid. Not worth it, especially when in the |
| // common case nothing has changed. |
| unchanged := lastImportGraph != nil && len(deps) == len(lastImportGraph.deps) |
| var ids []PackageID |
| for id, key := range deps { |
| ids = append(ids, id) |
| if unchanged { |
| prevKey, ok := lastImportGraph.deps[id] |
| unchanged = ok && prevKey == key |
| } |
| } |
| |
| if unchanged { |
| return lastImportGraph, nil |
| } |
| |
| b, err := s.forEachPackageInternal(ctx, nil, ids, nil, nil, nil) |
| if err != nil { |
| return nil, err |
| } |
| |
| next := &importGraph{ |
| fset: b.fset, |
| deps: deps, |
| imports: make(map[PackageID]pkgOrErr), |
| } |
| for id, fut := range b.importPackages { |
| if fut.v.pkg == nil && fut.v.err == nil { |
| panic(fmt.Sprintf("internal error: import node %s is not evaluated", id)) |
| } |
| next.imports[id] = fut.v |
| } |
| return next, nil |
| } |
| |
| // An importGraph holds selected results of a type-checking pass, to be re-used |
| // by subsequent snapshots. |
| type importGraph struct { |
| fset *token.FileSet // fileset used for type checking imports |
| deps map[PackageID]source.Hash // hash of direct dependencies for this graph |
| imports map[PackageID]pkgOrErr // results of type checking |
| } |
| |
| // Package visiting functions used by forEachPackage; see the documentation of |
| // forEachPackage for details. |
| type ( |
| preTypeCheck = func(int, *packageHandle) bool // false => don't type check |
| postTypeCheck = func(int, *Package) |
| ) |
| |
| // forEachPackage does a pre- and post- order traversal of the packages |
| // specified by ids using the provided pre and post functions. |
| // |
| // The pre func is is optional. If set, pre is evaluated after the package |
| // handle has been constructed, but before type-checking. If pre returns false, |
| // type-checking is skipped for this package handle. |
| // |
| // post is called with a syntax package after type-checking completes |
| // successfully. It is only called if pre returned true. |
| // |
| // Both pre and post may be called concurrently. |
| func (s *snapshot) forEachPackage(ctx context.Context, ids []PackageID, pre preTypeCheck, post postTypeCheck) error { |
| ctx, done := event.Start(ctx, "cache.forEachPackage", tag.PackageCount.Of(len(ids))) |
| defer done() |
| |
| if len(ids) == 0 { |
| return nil // short cut: many call sites do not handle empty ids |
| } |
| |
| impGraph := s.getImportGraph(ctx) |
| _, err := s.forEachPackageInternal(ctx, impGraph, nil, ids, pre, post) |
| return err |
| } |
| |
| // forEachPackageInternal is used by both forEachPackage and loadImportGraph to |
| // type-check a graph of packages. |
| // |
| // If a non-nil importGraph is provided, imports in this graph will be reused. |
| func (s *snapshot) forEachPackageInternal(ctx context.Context, importGraph *importGraph, importIDs, syntaxIDs []PackageID, pre preTypeCheck, post postTypeCheck) (*typeCheckBatch, error) { |
| b := &typeCheckBatch{ |
| s: s, |
| pre: pre, |
| post: post, |
| fset: fileSetWithBase(reservedForParsing), |
| syntaxIndex: make(map[PackageID]int), |
| cpulimit: make(chan struct{}, runtime.GOMAXPROCS(0)), |
| syntaxPackages: make(map[PackageID]*futurePackage), |
| importPackages: make(map[PackageID]*futurePackage), |
| } |
| |
| if importGraph != nil { |
| // Clone the file set every time, to ensure we do not leak files. |
| b.fset = tokeninternal.CloneFileSet(importGraph.fset) |
| // Pre-populate future cache with 'done' futures. |
| done := make(chan struct{}) |
| close(done) |
| for id, res := range importGraph.imports { |
| b.importPackages[id] = &futurePackage{done, res} |
| } |
| } else { |
| b.fset = fileSetWithBase(reservedForParsing) |
| } |
| |
| // Capture metadata once to avoid locking the snapshot when accessing |
| // metadata. |
| s.mu.Lock() |
| b.meta = s.meta |
| s.mu.Unlock() |
| |
| for i, id := range syntaxIDs { |
| b.syntaxIndex[id] = i |
| } |
| |
| // Start a single goroutine for each requested package. |
| // |
| // Other packages are reached recursively, and will not be evaluated if they |
| // are not needed. |
| var g errgroup.Group |
| for _, id := range importIDs { |
| id := id |
| g.Go(func() error { |
| _, err := b.getImportPackage(ctx, id) |
| return err |
| }) |
| } |
| for i, id := range syntaxIDs { |
| i := i |
| id := id |
| g.Go(func() error { |
| _, err := b.handleSyntaxPackage(ctx, i, id) |
| return err |
| }) |
| } |
| return b, g.Wait() |
| } |
| |
| // TODO(rfindley): re-order the declarations below to read better from top-to-bottom. |
| |
| // getImportPackage returns the *types.Package to use for importing the |
| // package referenced by id. |
| // |
| // This may be the package produced by type-checking syntax (as in the case |
| // where id is in the set of requested IDs), a package loaded from export data, |
| // or a package type-checked for import only. |
| func (b *typeCheckBatch) getImportPackage(ctx context.Context, id PackageID) (pkg *types.Package, err error) { |
| b.mu.Lock() |
| f, ok := b.importPackages[id] |
| if ok { |
| b.mu.Unlock() |
| |
| select { |
| case <-ctx.Done(): |
| return nil, ctx.Err() |
| case <-f.done: |
| return f.v.pkg, f.v.err |
| } |
| } |
| |
| f = &futurePackage{done: make(chan struct{})} |
| b.importPackages[id] = f |
| b.mu.Unlock() |
| |
| defer func() { |
| f.v = pkgOrErr{pkg, err} |
| close(f.done) |
| }() |
| |
| if index, ok := b.syntaxIndex[id]; ok { |
| pkg, err := b.handleSyntaxPackage(ctx, index, id) |
| if err != nil { |
| return nil, err |
| } |
| if pkg != nil { |
| return pkg, nil |
| } |
| // type-checking was short-circuited by the pre- func. |
| } |
| |
| // unsafe cannot be imported or type-checked. |
| if id == "unsafe" { |
| return types.Unsafe, nil |
| } |
| |
| ph, err := b.s.buildPackageHandle(ctx, id) |
| if err != nil { |
| return nil, err |
| } |
| |
| data, err := filecache.Get(exportDataKind, ph.key) |
| if err == filecache.ErrNotFound { |
| // No cached export data: type-check as fast as possible. |
| return b.checkPackageForImport(ctx, ph) |
| } |
| if err != nil { |
| return nil, fmt.Errorf("failed to read cache data for %s: %v", ph.m.ID, err) |
| } |
| return b.importPackage(ctx, ph.m, data) |
| } |
| |
| // handleSyntaxPackage handles one package from the ids slice. |
| // |
| // If type checking occurred while handling the package, it returns the |
| // resulting types.Package so that it may be used for importing. |
| // |
| // handleSyntaxPackage returns (nil, nil) if pre returned false. |
| func (b *typeCheckBatch) handleSyntaxPackage(ctx context.Context, i int, id PackageID) (pkg *types.Package, err error) { |
| b.mu.Lock() |
| f, ok := b.syntaxPackages[id] |
| if ok { |
| b.mu.Unlock() |
| <-f.done |
| return f.v.pkg, f.v.err |
| } |
| |
| f = &futurePackage{done: make(chan struct{})} |
| b.syntaxPackages[id] = f |
| b.mu.Unlock() |
| defer func() { |
| f.v = pkgOrErr{pkg, err} |
| close(f.done) |
| }() |
| |
| ph, err := b.s.buildPackageHandle(ctx, id) |
| if err != nil { |
| return nil, err |
| } |
| |
| if b.pre != nil && !b.pre(i, ph) { |
| return nil, nil // skip: export data only |
| } |
| |
| if err := b.awaitPredecessors(ctx, ph.m); err != nil { |
| // One failed precessesor should not fail the entire type checking |
| // operation. Errors related to imports will be reported as type checking |
| // diagnostics. |
| if ctx.Err() != nil { |
| return nil, ctx.Err() |
| } |
| } |
| |
| // Wait to acquire a CPU token. |
| // |
| // Note: it is important to acquire this token only after awaiting |
| // predecessors, to avoid starvation. |
| select { |
| case <-ctx.Done(): |
| return nil, ctx.Err() |
| case b.cpulimit <- struct{}{}: |
| defer func() { |
| <-b.cpulimit // release CPU token |
| }() |
| } |
| |
| // We need a syntax package. |
| syntaxPkg, err := b.checkPackage(ctx, ph) |
| if err != nil { |
| return nil, err |
| } |
| b.post(i, syntaxPkg) |
| return syntaxPkg.pkg.types, nil |
| } |
| |
| // importPackage loads the given package from its export data in p.exportData |
| // (which must already be populated). |
| func (b *typeCheckBatch) importPackage(ctx context.Context, m *source.Metadata, data []byte) (*types.Package, error) { |
| ctx, done := event.Start(ctx, "cache.typeCheckBatch.importPackage", tag.Package.Of(string(m.ID))) |
| defer done() |
| |
| impMap := b.importMap(m.ID) |
| |
| var firstErr error // TODO(rfindley): unused: revisit or remove. |
| thisPackage := types.NewPackage(string(m.PkgPath), string(m.Name)) |
| getPackage := func(path, name string) *types.Package { |
| if path == string(m.PkgPath) { |
| return thisPackage |
| } |
| |
| id := impMap[path] |
| imp, err := b.getImportPackage(ctx, id) |
| if err == nil { |
| return imp |
| } |
| // inv: err != nil |
| if firstErr == nil { |
| firstErr = err |
| } |
| |
| // Context cancellation, or a very bad error such as a file permission |
| // error. |
| // |
| // Returning nil here will cause the import to fail (and panic if |
| // gcimporter.debug is set), but that is preferable to the confusing errors |
| // produced when shallow import encounters an empty package. |
| return nil |
| } |
| |
| // Importing is potentially expensive, and might not encounter cancellations |
| // via dependencies (e.g. if they have already been evaluated). |
| if ctx.Err() != nil { |
| return nil, ctx.Err() |
| } |
| |
| // TODO(rfindley): collect "deep" hashes here using the provided |
| // callback, for precise pruning. |
| imported, err := gcimporter.IImportShallow(b.fset, getPackage, data, string(m.PkgPath), func(*types.Package, string) {}) |
| if err != nil { |
| return nil, fmt.Errorf("import failed for %q: %v", m.ID, err) |
| } |
| return imported, nil |
| } |
| |
| // checkPackageForImport type checks, but skips function bodies and does not |
| // record syntax information. |
| func (b *typeCheckBatch) checkPackageForImport(ctx context.Context, ph *packageHandle) (*types.Package, error) { |
| ctx, done := event.Start(ctx, "cache.typeCheckBatch.checkPackageForImport", tag.Package.Of(string(ph.m.ID))) |
| defer done() |
| |
| onError := func(e error) { |
| // Ignore errors for exporting. |
| } |
| cfg := b.typesConfig(ctx, ph.inputs, onError) |
| cfg.IgnoreFuncBodies = true |
| pgfs, err := b.s.parseCache.parseFiles(ctx, b.fset, source.ParseFull, ph.inputs.compiledGoFiles...) |
| if err != nil { |
| return nil, err |
| } |
| pkg := types.NewPackage(string(ph.inputs.pkgPath), string(ph.inputs.name)) |
| check := types.NewChecker(cfg, b.fset, pkg, nil) |
| |
| files := make([]*ast.File, len(pgfs)) |
| for i, pgf := range pgfs { |
| files[i] = pgf.File |
| } |
| |
| // Type checking is expensive, and we may not have ecountered cancellations |
| // via parsing (e.g. if we got nothing but cache hits for parsed files). |
| if ctx.Err() != nil { |
| return nil, ctx.Err() |
| } |
| |
| _ = check.Files(files) // ignore errors |
| |
| // If the context was cancelled, we may have returned a ton of transient |
| // errors to the type checker. Swallow them. |
| if ctx.Err() != nil { |
| return nil, ctx.Err() |
| } |
| |
| // Asynchronously record export data. |
| go func() { |
| exportData, err := gcimporter.IExportShallow(b.fset, pkg) |
| if err != nil { |
| bug.Reportf("exporting package %v: %v", ph.m.ID, err) |
| return |
| } |
| if err := filecache.Set(exportDataKind, ph.key, exportData); err != nil { |
| event.Error(ctx, fmt.Sprintf("storing export data for %s", ph.m.ID), err) |
| } |
| }() |
| return pkg, nil |
| } |
| |
| // checkPackage "fully type checks" to produce a syntax package. |
| func (b *typeCheckBatch) checkPackage(ctx context.Context, ph *packageHandle) (*Package, error) { |
| ctx, done := event.Start(ctx, "cache.typeCheckBatch.checkPackage", tag.Package.Of(string(ph.m.ID))) |
| defer done() |
| |
| // TODO(rfindley): refactor to inline typeCheckImpl here. There is no need |
| // for so many layers to build up the package |
| // (checkPackage->typeCheckImpl->doTypeCheck). |
| pkg, err := typeCheckImpl(ctx, b, ph.inputs) |
| |
| if err == nil { |
| // Write package data to disk asynchronously. |
| go func() { |
| toCache := map[string][]byte{ |
| xrefsKind: pkg.xrefs, |
| methodSetsKind: pkg.methodsets.Encode(), |
| diagnosticsKind: encodeDiagnostics(pkg.diagnostics), |
| } |
| |
| if ph.m.ID != "unsafe" { // unsafe cannot be exported |
| exportData, err := gcimporter.IExportShallow(pkg.fset, pkg.types) |
| if err != nil { |
| bug.Reportf("exporting package %v: %v", ph.m.ID, err) |
| } else { |
| toCache[exportDataKind] = exportData |
| } |
| } |
| |
| for kind, data := range toCache { |
| if err := filecache.Set(kind, ph.key, data); err != nil { |
| event.Error(ctx, fmt.Sprintf("storing %s data for %s", kind, ph.m.ID), err) |
| } |
| } |
| }() |
| } |
| |
| return &Package{ph.m, pkg}, err |
| } |
| |
| // awaitPredecessors awaits all packages for m.DepsByPkgPath, returning an |
| // error if awaiting failed due to context cancellation or if there was an |
| // unrecoverable error loading export data. |
| // |
| // TODO(rfindley): inline, now that this is only called in one place. |
| func (b *typeCheckBatch) awaitPredecessors(ctx context.Context, m *source.Metadata) error { |
| // await predecessors concurrently, as some of them may be non-syntax |
| // packages, and therefore will not have been started by the type-checking |
| // batch. |
| var g errgroup.Group |
| for _, depID := range m.DepsByPkgPath { |
| depID := depID |
| g.Go(func() error { |
| _, err := b.getImportPackage(ctx, depID) |
| return err |
| }) |
| } |
| return g.Wait() |
| } |
| |
| // importMap returns the map of package path -> package ID relative to the |
| // specified ID. |
| func (b *typeCheckBatch) importMap(id PackageID) map[string]source.PackageID { |
| impMap := make(map[string]source.PackageID) |
| var populateDeps func(m *source.Metadata) |
| populateDeps = func(parent *source.Metadata) { |
| for _, id := range parent.DepsByPkgPath { |
| m := b.meta.metadata[id] |
| if _, ok := impMap[string(m.PkgPath)]; ok { |
| continue |
| } |
| impMap[string(m.PkgPath)] = m.ID |
| populateDeps(m) |
| } |
| } |
| m := b.meta.metadata[id] |
| populateDeps(m) |
| return impMap |
| } |
| |
| // A packageHandle holds package information, some of which may not be fully |
| // evaluated. |
| // |
| // The only methods on packageHandle that are safe to call before calling await |
| // are Metadata and await itself. |
| type packageHandle struct { |
| m *source.Metadata |
| |
| inputs typeCheckInputs |
| |
| // key is the hashed key for the package. |
| // |
| // It includes the all bits of the transitive closure of |
| // dependencies's sources. This is more than type checking |
| // really depends on: export data of direct deps should be |
| // enough. (The key for analysis actions could similarly |
| // hash only Facts of direct dependencies.) |
| key source.Hash |
| } |
| |
| // buildPackageHandle returns a handle for the future results of |
| // type-checking the package identified by id in the given mode. |
| // It assumes that the given ID already has metadata available, so it does not |
| // attempt to reload missing or invalid metadata. The caller must reload |
| // metadata if needed. |
| func (s *snapshot) buildPackageHandle(ctx context.Context, id PackageID) (*packageHandle, error) { |
| s.mu.Lock() |
| entry, hit := s.packages.Get(id) |
| m := s.meta.metadata[id] |
| s.mu.Unlock() |
| |
| if m == nil { |
| return nil, fmt.Errorf("no metadata for %s", id) |
| } |
| |
| if hit { |
| return entry.(*packageHandle), nil |
| } |
| |
| inputs, err := s.typeCheckInputs(ctx, m) |
| if err != nil { |
| return nil, err |
| } |
| // All the file reading has now been done. |
| // Create a handle for the result of type checking. |
| phKey := computePackageKey(s, inputs) |
| ph := &packageHandle{ |
| m: m, |
| inputs: inputs, |
| key: phKey, |
| } |
| |
| s.mu.Lock() |
| defer s.mu.Unlock() |
| |
| // Check that the metadata has not changed |
| // (which should invalidate this handle). |
| // |
| // (In future, handles should form a graph with edges from a |
| // packageHandle to the handles for parsing its files and the |
| // handles for type-checking its immediate deps, at which |
| // point there will be no need to even access s.meta.) |
| if s.meta.metadata[ph.m.ID] != ph.m { |
| // TODO(rfindley): this should be bug.Errorf. |
| return nil, fmt.Errorf("stale metadata for %s", ph.m.ID) |
| } |
| |
| // Check cache again in case another goroutine got there first. |
| if prev, ok := s.packages.Get(id); ok { |
| prevPH := prev.(*packageHandle) |
| if prevPH.m != ph.m { |
| return nil, bug.Errorf("existing package handle does not match for %s", ph.m.ID) |
| } |
| return prevPH, nil |
| } |
| |
| s.packages.Set(id, ph, nil) |
| return ph, nil |
| } |
| |
| // typeCheckInputs contains the inputs of a call to typeCheckImpl, which |
| // type-checks a package. |
| // |
| // Part of the purpose of this type is to keep type checking in-sync with the |
| // package handle key, by explicitly identifying the inputs to type checking. |
| type typeCheckInputs struct { |
| id PackageID |
| |
| // Used for type checking: |
| pkgPath PackagePath |
| name PackageName |
| goFiles, compiledGoFiles []source.FileHandle |
| sizes types.Sizes |
| deps map[PackageID]*packageHandle |
| depsByImpPath map[ImportPath]PackageID |
| goVersion string // packages.Module.GoVersion, e.g. "1.18" |
| |
| // Used for type check diagnostics: |
| relatedInformation bool |
| linkTarget string |
| moduleMode bool |
| } |
| |
| func (s *snapshot) typeCheckInputs(ctx context.Context, m *source.Metadata) (typeCheckInputs, error) { |
| deps := make(map[PackageID]*packageHandle) |
| for _, depID := range m.DepsByPkgPath { |
| depHandle, err := s.buildPackageHandle(ctx, depID) |
| if err != nil { |
| // If err is non-nil, we either have an invalid dependency, or a |
| // catastrophic failure to read a file (context cancellation or |
| // permission issues). |
| // |
| // We don't want one bad dependency to prevent us from type-checking the |
| // package -- we should instead get an import error. So we only abort |
| // this operation if the context is cancelled. |
| // |
| // We could do a better job of handling permission errors on files, but |
| // this is rare, and it is reasonable to treat the same an invalid |
| // dependency. |
| event.Error(ctx, fmt.Sprintf("%s: no dep handle for %s", m.ID, depID), err, source.SnapshotLabels(s)...) |
| if ctx.Err() != nil { |
| return typeCheckInputs{}, ctx.Err() // cancelled |
| } |
| continue |
| } |
| deps[depID] = depHandle |
| } |
| |
| // Read both lists of files of this package. |
| // |
| // Parallelism is not necessary here as the files will have already been |
| // pre-read at load time. |
| // |
| // goFiles aren't presented to the type checker--nor |
| // are they included in the key, unsoundly--but their |
| // syntax trees are available from (*pkg).File(URI). |
| // TODO(adonovan): consider parsing them on demand? |
| // The need should be rare. |
| goFiles, err := readFiles(ctx, s, m.GoFiles) |
| if err != nil { |
| return typeCheckInputs{}, err |
| } |
| compiledGoFiles, err := readFiles(ctx, s, m.CompiledGoFiles) |
| if err != nil { |
| return typeCheckInputs{}, err |
| } |
| |
| goVersion := "" |
| if m.Module != nil && m.Module.GoVersion != "" { |
| goVersion = m.Module.GoVersion |
| } |
| |
| return typeCheckInputs{ |
| id: m.ID, |
| pkgPath: m.PkgPath, |
| name: m.Name, |
| goFiles: goFiles, |
| compiledGoFiles: compiledGoFiles, |
| sizes: m.TypesSizes, |
| deps: deps, |
| depsByImpPath: m.DepsByImpPath, |
| goVersion: goVersion, |
| |
| relatedInformation: s.view.Options().RelatedInformationSupported, |
| linkTarget: s.view.Options().LinkTarget, |
| moduleMode: s.moduleMode(), |
| }, nil |
| } |
| |
| // readFiles reads the content of each file URL from the source |
| // (e.g. snapshot or cache). |
| func readFiles(ctx context.Context, fs source.FileSource, uris []span.URI) (_ []source.FileHandle, err error) { |
| fhs := make([]source.FileHandle, len(uris)) |
| for i, uri := range uris { |
| fhs[i], err = fs.ReadFile(ctx, uri) |
| if err != nil { |
| return nil, err |
| } |
| } |
| return fhs, nil |
| } |
| |
| // computePackageKey returns a key representing the act of type checking |
| // a package named id containing the specified files, metadata, and |
| // combined dependency hash. |
| func computePackageKey(s *snapshot, inputs typeCheckInputs) source.Hash { |
| hasher := sha256.New() |
| |
| // In principle, a key must be the hash of an |
| // unambiguous encoding of all the relevant data. |
| // If it's ambiguous, we risk collisions. |
| |
| // package identifiers |
| fmt.Fprintf(hasher, "package: %s %s %s\n", inputs.id, inputs.name, inputs.pkgPath) |
| |
| // module Go version |
| fmt.Fprintf(hasher, "go %s\n", inputs.goVersion) |
| |
| // import map |
| importPaths := make([]string, 0, len(inputs.depsByImpPath)) |
| for impPath := range inputs.depsByImpPath { |
| importPaths = append(importPaths, string(impPath)) |
| } |
| sort.Strings(importPaths) |
| for _, impPath := range importPaths { |
| fmt.Fprintf(hasher, "import %s %s", impPath, string(inputs.depsByImpPath[ImportPath(impPath)])) |
| } |
| |
| // deps, in PackageID order |
| depIDs := make([]string, 0, len(inputs.deps)) |
| for depID := range inputs.deps { |
| depIDs = append(depIDs, string(depID)) |
| } |
| sort.Strings(depIDs) |
| for _, depID := range depIDs { |
| dep := inputs.deps[PackageID(depID)] |
| fmt.Fprintf(hasher, "dep: %s key:%s\n", dep.m.PkgPath, dep.key) |
| } |
| |
| // file names and contents |
| fmt.Fprintf(hasher, "compiledGoFiles: %d\n", len(inputs.compiledGoFiles)) |
| for _, fh := range inputs.compiledGoFiles { |
| fmt.Fprintln(hasher, fh.FileIdentity()) |
| } |
| fmt.Fprintf(hasher, "goFiles: %d\n", len(inputs.goFiles)) |
| for _, fh := range inputs.goFiles { |
| fmt.Fprintln(hasher, fh.FileIdentity()) |
| } |
| |
| // types sizes |
| sz := inputs.sizes.(*types.StdSizes) |
| fmt.Fprintf(hasher, "sizes: %d %d\n", sz.WordSize, sz.MaxAlign) |
| |
| fmt.Fprintf(hasher, "relatedInformation: %t\n", inputs.relatedInformation) |
| fmt.Fprintf(hasher, "linkTarget: %s\n", inputs.linkTarget) |
| fmt.Fprintf(hasher, "moduleMode: %t\n", inputs.moduleMode) |
| |
| var hash [sha256.Size]byte |
| hasher.Sum(hash[:0]) |
| return hash |
| } |
| |
| // typeCheckImpl type checks the parsed source files in compiledGoFiles. |
| // (The resulting pkg also holds the parsed but not type-checked goFiles.) |
| // deps holds the future results of type-checking the direct dependencies. |
| func typeCheckImpl(ctx context.Context, b *typeCheckBatch, inputs typeCheckInputs) (*syntaxPackage, error) { |
| ctx, done := event.Start(ctx, "cache.typeCheck", tag.Package.Of(string(inputs.id))) |
| defer done() |
| |
| pkg, err := doTypeCheck(ctx, b, inputs) |
| if err != nil { |
| return nil, err |
| } |
| pkg.methodsets = methodsets.NewIndex(pkg.fset, pkg.types) |
| pkg.xrefs = xrefs.Index(pkg.compiledGoFiles, pkg.types, pkg.typesInfo) |
| |
| // Our heuristic for whether to show type checking errors is: |
| // + If any file was 'fixed', don't show type checking errors as we |
| // can't guarantee that they reference accurate locations in the source. |
| // + If there is a parse error _in the current file_, suppress type |
| // errors in that file. |
| // + Otherwise, show type errors even in the presence of parse errors in |
| // other package files. go/types attempts to suppress follow-on errors |
| // due to bad syntax, so on balance type checking errors still provide |
| // a decent signal/noise ratio as long as the file in question parses. |
| |
| // Track URIs with parse errors so that we can suppress type errors for these |
| // files. |
| unparseable := map[span.URI]bool{} |
| for _, e := range pkg.parseErrors { |
| diags, err := parseErrorDiagnostics(pkg, e) |
| if err != nil { |
| event.Error(ctx, "unable to compute positions for parse errors", err, tag.Package.Of(string(inputs.id))) |
| continue |
| } |
| for _, diag := range diags { |
| unparseable[diag.URI] = true |
| pkg.diagnostics = append(pkg.diagnostics, diag) |
| } |
| } |
| |
| if pkg.hasFixedFiles { |
| return pkg, nil |
| } |
| |
| unexpanded := pkg.typeErrors |
| pkg.typeErrors = nil |
| for _, e := range expandErrors(unexpanded, inputs.relatedInformation) { |
| diags, err := typeErrorDiagnostics(inputs.moduleMode, inputs.linkTarget, pkg, e) |
| if err != nil { |
| // If we fail here and there are no parse errors, it means we are hiding |
| // a valid type-checking error from the user. This must be a bug. |
| if len(pkg.parseErrors) == 0 { |
| bug.Reportf("failed to compute position for type error %v: %v", e, err) |
| } |
| continue |
| } |
| pkg.typeErrors = append(pkg.typeErrors, e.primary) |
| for _, diag := range diags { |
| // If the file didn't parse cleanly, it is highly likely that type |
| // checking errors will be confusing or redundant. But otherwise, type |
| // checking usually provides a good enough signal to include. |
| if !unparseable[diag.URI] { |
| pkg.diagnostics = append(pkg.diagnostics, diag) |
| } |
| } |
| } |
| |
| return pkg, nil |
| } |
| |
| var goVersionRx = regexp.MustCompile(`^go([1-9][0-9]*)\.(0|[1-9][0-9]*)$`) |
| |
| func doTypeCheck(ctx context.Context, b *typeCheckBatch, inputs typeCheckInputs) (*syntaxPackage, error) { |
| pkg := &syntaxPackage{ |
| id: inputs.id, |
| fset: b.fset, // must match parse call below |
| types: types.NewPackage(string(inputs.pkgPath), string(inputs.name)), |
| typesInfo: &types.Info{ |
| Types: make(map[ast.Expr]types.TypeAndValue), |
| Defs: make(map[*ast.Ident]types.Object), |
| Uses: make(map[*ast.Ident]types.Object), |
| Implicits: make(map[ast.Node]types.Object), |
| Selections: make(map[*ast.SelectorExpr]*types.Selection), |
| Scopes: make(map[ast.Node]*types.Scope), |
| }, |
| } |
| typeparams.InitInstanceInfo(pkg.typesInfo) |
| |
| // Collect parsed files from the type check pass, capturing parse errors from |
| // compiled files. |
| var err error |
| pkg.goFiles, err = b.s.parseCache.parseFiles(ctx, b.fset, source.ParseFull, inputs.goFiles...) |
| if err != nil { |
| return nil, err |
| } |
| pkg.compiledGoFiles, err = b.s.parseCache.parseFiles(ctx, b.fset, source.ParseFull, inputs.compiledGoFiles...) |
| if err != nil { |
| return nil, err |
| } |
| for _, pgf := range pkg.compiledGoFiles { |
| if pgf.ParseErr != nil { |
| pkg.parseErrors = append(pkg.parseErrors, pgf.ParseErr) |
| } |
| } |
| |
| // Use the default type information for the unsafe package. |
| if inputs.pkgPath == "unsafe" { |
| // Don't type check Unsafe: it's unnecessary, and doing so exposes a data |
| // race to Unsafe.completed. |
| pkg.types = types.Unsafe |
| return pkg, nil |
| } |
| |
| if len(pkg.compiledGoFiles) == 0 { |
| // No files most likely means go/packages failed. |
| // |
| // TODO(rfindley): in the past, we would capture go list errors in this |
| // case, to present go list errors to the user. However we had no tests for |
| // this behavior. It is unclear if anything better can be done here. |
| return nil, fmt.Errorf("no parsed files for package %s", inputs.pkgPath) |
| } |
| |
| onError := func(e error) { |
| pkg.typeErrors = append(pkg.typeErrors, e.(types.Error)) |
| } |
| cfg := b.typesConfig(ctx, inputs, onError) |
| |
| check := types.NewChecker(cfg, pkg.fset, pkg.types, pkg.typesInfo) |
| |
| var files []*ast.File |
| for _, cgf := range pkg.compiledGoFiles { |
| files = append(files, cgf.File) |
| } |
| |
| // Type checking is expensive, and we may not have ecountered cancellations |
| // via parsing (e.g. if we got nothing but cache hits for parsed files). |
| if ctx.Err() != nil { |
| return nil, ctx.Err() |
| } |
| |
| // Type checking errors are handled via the config, so ignore them here. |
| _ = check.Files(files) // 50us-15ms, depending on size of package |
| |
| // If the context was cancelled, we may have returned a ton of transient |
| // errors to the type checker. Swallow them. |
| if ctx.Err() != nil { |
| return nil, ctx.Err() |
| } |
| |
| // Collect imports by package path for the DependencyTypes API. |
| pkg.importMap = make(map[PackagePath]*types.Package) |
| var collectDeps func(*types.Package) |
| collectDeps = func(p *types.Package) { |
| pkgPath := PackagePath(p.Path()) |
| if _, ok := pkg.importMap[pkgPath]; ok { |
| return |
| } |
| pkg.importMap[pkgPath] = p |
| for _, imp := range p.Imports() { |
| collectDeps(imp) |
| } |
| } |
| collectDeps(pkg.types) |
| |
| return pkg, nil |
| } |
| |
| func (b *typeCheckBatch) typesConfig(ctx context.Context, inputs typeCheckInputs, onError func(e error)) *types.Config { |
| cfg := &types.Config{ |
| Sizes: inputs.sizes, |
| Error: onError, |
| Importer: importerFunc(func(path string) (*types.Package, error) { |
| // While all of the import errors could be reported |
| // based on the metadata before we start type checking, |
| // reporting them via types.Importer places the errors |
| // at the correct source location. |
| id, ok := inputs.depsByImpPath[ImportPath(path)] |
| if !ok { |
| // If the import declaration is broken, |
| // go list may fail to report metadata about it. |
| // See TestFixImportDecl for an example. |
| return nil, fmt.Errorf("missing metadata for import of %q", path) |
| } |
| depPH := inputs.deps[id] |
| if depPH == nil { |
| // e.g. missing metadata for dependencies in buildPackageHandle |
| return nil, missingPkgError(path, inputs.moduleMode) |
| } |
| if !source.IsValidImport(inputs.pkgPath, depPH.m.PkgPath) { |
| return nil, fmt.Errorf("invalid use of internal package %q", path) |
| } |
| return b.getImportPackage(ctx, id) |
| }), |
| } |
| |
| if inputs.goVersion != "" { |
| goVersion := "go" + inputs.goVersion |
| // types.NewChecker panics if GoVersion is invalid. An unparsable mod |
| // file should probably stop us before we get here, but double check |
| // just in case. |
| if goVersionRx.MatchString(goVersion) { |
| typesinternal.SetGoVersion(cfg, goVersion) |
| } |
| } |
| |
| // We want to type check cgo code if go/types supports it. |
| // We passed typecheckCgo to go/packages when we Loaded. |
| typesinternal.SetUsesCgo(cfg) |
| return cfg |
| } |
| |
| // depsErrors creates diagnostics for each metadata error (e.g. import cycle). |
| // These may be attached to import declarations in the transitive source files |
| // of pkg, or to 'requires' declarations in the package's go.mod file. |
| // |
| // TODO(rfindley): move this to load.go |
| func depsErrors(ctx context.Context, m *source.Metadata, meta *metadataGraph, fs source.FileSource, workspacePackages map[PackageID]PackagePath) ([]*source.Diagnostic, error) { |
| // Select packages that can't be found, and were imported in non-workspace packages. |
| // Workspace packages already show their own errors. |
| var relevantErrors []*packagesinternal.PackageError |
| for _, depsError := range m.DepsErrors { |
| // Up to Go 1.15, the missing package was included in the stack, which |
| // was presumably a bug. We want the next one up. |
| directImporterIdx := len(depsError.ImportStack) - 1 |
| if directImporterIdx < 0 { |
| continue |
| } |
| |
| directImporter := depsError.ImportStack[directImporterIdx] |
| if _, ok := workspacePackages[PackageID(directImporter)]; ok { |
| continue |
| } |
| relevantErrors = append(relevantErrors, depsError) |
| } |
| |
| // Don't build the import index for nothing. |
| if len(relevantErrors) == 0 { |
| return nil, nil |
| } |
| |
| // Subsequent checks require Go files. |
| if len(m.CompiledGoFiles) == 0 { |
| return nil, nil |
| } |
| |
| // Build an index of all imports in the package. |
| type fileImport struct { |
| cgf *source.ParsedGoFile |
| imp *ast.ImportSpec |
| } |
| allImports := map[string][]fileImport{} |
| for _, uri := range m.CompiledGoFiles { |
| pgf, err := parseGoURI(ctx, fs, uri, source.ParseHeader) |
| if err != nil { |
| return nil, err |
| } |
| fset := tokeninternal.FileSetFor(pgf.Tok) |
| // TODO(adonovan): modify Imports() to accept a single token.File (cgf.Tok). |
| for _, group := range astutil.Imports(fset, pgf.File) { |
| for _, imp := range group { |
| if imp.Path == nil { |
| continue |
| } |
| path := strings.Trim(imp.Path.Value, `"`) |
| allImports[path] = append(allImports[path], fileImport{pgf, imp}) |
| } |
| } |
| } |
| |
| // Apply a diagnostic to any import involved in the error, stopping once |
| // we reach the workspace. |
| var errors []*source.Diagnostic |
| for _, depErr := range relevantErrors { |
| for i := len(depErr.ImportStack) - 1; i >= 0; i-- { |
| item := depErr.ImportStack[i] |
| if _, ok := workspacePackages[PackageID(item)]; ok { |
| break |
| } |
| |
| for _, imp := range allImports[item] { |
| rng, err := imp.cgf.NodeRange(imp.imp) |
| if err != nil { |
| return nil, err |
| } |
| fixes, err := goGetQuickFixes(m.Module != nil, imp.cgf.URI, item) |
| if err != nil { |
| return nil, err |
| } |
| errors = append(errors, &source.Diagnostic{ |
| URI: imp.cgf.URI, |
| Range: rng, |
| Severity: protocol.SeverityError, |
| Source: source.TypeError, |
| Message: fmt.Sprintf("error while importing %v: %v", item, depErr.Err), |
| SuggestedFixes: fixes, |
| }) |
| } |
| } |
| } |
| |
| modFile, err := nearestModFile(ctx, m.CompiledGoFiles[0], fs) |
| if err != nil { |
| return nil, err |
| } |
| pm, err := parseModURI(ctx, fs, modFile) |
| if err != nil { |
| return nil, err |
| } |
| |
| // Add a diagnostic to the module that contained the lowest-level import of |
| // the missing package. |
| for _, depErr := range relevantErrors { |
| for i := len(depErr.ImportStack) - 1; i >= 0; i-- { |
| item := depErr.ImportStack[i] |
| m := meta.metadata[PackageID(item)] |
| if m == nil || m.Module == nil { |
| continue |
| } |
| modVer := module.Version{Path: m.Module.Path, Version: m.Module.Version} |
| reference := findModuleReference(pm.File, modVer) |
| if reference == nil { |
| continue |
| } |
| rng, err := pm.Mapper.OffsetRange(reference.Start.Byte, reference.End.Byte) |
| if err != nil { |
| return nil, err |
| } |
| fixes, err := goGetQuickFixes(true, pm.URI, item) |
| if err != nil { |
| return nil, err |
| } |
| errors = append(errors, &source.Diagnostic{ |
| URI: pm.URI, |
| Range: rng, |
| Severity: protocol.SeverityError, |
| Source: source.TypeError, |
| Message: fmt.Sprintf("error while importing %v: %v", item, depErr.Err), |
| SuggestedFixes: fixes, |
| }) |
| break |
| } |
| } |
| return errors, nil |
| } |
| |
| // missingPkgError returns an error message for a missing package that varies |
| // based on the user's workspace mode. |
| func missingPkgError(pkgPath string, moduleMode bool) error { |
| // TODO(rfindley): improve this error. Previous versions of this error had |
| // access to the full snapshot, and could provide more information (such as |
| // the initialization error). |
| if moduleMode { |
| // Previously, we would present the initialization error here. |
| return fmt.Errorf("no required module provides package %q", pkgPath) |
| } else { |
| // Previously, we would list the directories in GOROOT and GOPATH here. |
| return fmt.Errorf("cannot find package %q in GOROOT or GOPATH", pkgPath) |
| } |
| } |
| |
| type extendedError struct { |
| primary types.Error |
| secondaries []types.Error |
| } |
| |
| func (e extendedError) Error() string { |
| return e.primary.Error() |
| } |
| |
| // expandErrors duplicates "secondary" errors by mapping them to their main |
| // error. Some errors returned by the type checker are followed by secondary |
| // errors which give more information about the error. These are errors in |
| // their own right, and they are marked by starting with \t. For instance, when |
| // there is a multiply-defined function, the secondary error points back to the |
| // definition first noticed. |
| // |
| // This function associates the secondary error with its primary error, which can |
| // then be used as RelatedInformation when the error becomes a diagnostic. |
| // |
| // If supportsRelatedInformation is false, the secondary is instead embedded as |
| // additional context in the primary error. |
| func expandErrors(errs []types.Error, supportsRelatedInformation bool) []extendedError { |
| var result []extendedError |
| for i := 0; i < len(errs); { |
| original := extendedError{ |
| primary: errs[i], |
| } |
| for i++; i < len(errs); i++ { |
| spl := errs[i] |
| if len(spl.Msg) == 0 || spl.Msg[0] != '\t' { |
| break |
| } |
| spl.Msg = spl.Msg[1:] |
| original.secondaries = append(original.secondaries, spl) |
| } |
| |
| // Clone the error to all its related locations -- VS Code, at least, |
| // doesn't do it for us. |
| result = append(result, original) |
| for i, mainSecondary := range original.secondaries { |
| // Create the new primary error, with a tweaked message, in the |
| // secondary's location. We need to start from the secondary to |
| // capture its unexported location fields. |
| relocatedSecondary := mainSecondary |
| if supportsRelatedInformation { |
| relocatedSecondary.Msg = fmt.Sprintf("%v (see details)", original.primary.Msg) |
| } else { |
| relocatedSecondary.Msg = fmt.Sprintf("%v (this error: %v)", original.primary.Msg, mainSecondary.Msg) |
| } |
| relocatedSecondary.Soft = original.primary.Soft |
| |
| // Copy over the secondary errors, noting the location of the |
| // current error we're cloning. |
| clonedError := extendedError{primary: relocatedSecondary, secondaries: []types.Error{original.primary}} |
| for j, secondary := range original.secondaries { |
| if i == j { |
| secondary.Msg += " (this error)" |
| } |
| clonedError.secondaries = append(clonedError.secondaries, secondary) |
| } |
| result = append(result, clonedError) |
| } |
| |
| } |
| return result |
| } |
| |
| // An importFunc is an implementation of the single-method |
| // types.Importer interface based on a function value. |
| type importerFunc func(path string) (*types.Package, error) |
| |
| func (f importerFunc) Import(path string) (*types.Package, error) { return f(path) } |