internal/lsp: port fill struct into analysis framework
The current implementation of the fill struct tool is not a part of
the analysis framework. This commit moves the functionality from the
source directory to the analysis directory.
Change-Id: Ibe37b57f3e6680c8729932dbbe010a4642600e4a
Reviewed-on: https://go-review.googlesource.com/c/tools/+/237258
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/internal/lsp/analysis/fillstruct/fillstruct.go b/internal/lsp/analysis/fillstruct/fillstruct.go
new file mode 100644
index 0000000..b23a05f
--- /dev/null
+++ b/internal/lsp/analysis/fillstruct/fillstruct.go
@@ -0,0 +1,145 @@
+// Copyright 2020 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 fillstruct defines an Analyzer that automatically
+// fills in a struct declaration with zero value elements for each field.
+package fillstruct
+
+import (
+ "bytes"
+ "go/ast"
+ "go/format"
+ "go/types"
+ "strings"
+
+ "golang.org/x/tools/go/analysis"
+ "golang.org/x/tools/go/analysis/passes/inspect"
+ "golang.org/x/tools/go/ast/inspector"
+ "golang.org/x/tools/internal/analysisinternal"
+)
+
+const Doc = `suggested input for incomplete struct initializations
+
+This analyzer provides the appropriate zero values for all
+uninitialized fields of a struct. For example, given the following struct:
+ type Foo struct {
+ ID int64
+ Name string
+ }
+the initialization
+ var _ = Foo{}
+will turn into
+ var _ = Foo{
+ ID: 0,
+ Name: "",
+ }
+`
+
+var Analyzer = &analysis.Analyzer{
+ Name: "fillstruct",
+ Doc: Doc,
+ Requires: []*analysis.Analyzer{inspect.Analyzer},
+ Run: run,
+ RunDespiteErrors: true,
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+ inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+ nodeFilter := []ast.Node{(*ast.CompositeLit)(nil)}
+ inspect.Preorder(nodeFilter, func(n ast.Node) {
+ info := pass.TypesInfo
+ if info == nil {
+ return
+ }
+ expr := n.(*ast.CompositeLit)
+
+ // TODO: Handle partially-filled structs as well.
+ if len(expr.Elts) != 0 {
+ return
+ }
+
+ var file *ast.File
+ for _, f := range pass.Files {
+ if f.Pos() <= expr.Pos() && expr.Pos() <= f.End() {
+ file = f
+ break
+ }
+ }
+ if file == nil {
+ return
+ }
+
+ typ := info.TypeOf(expr)
+ if typ == nil {
+ return
+ }
+
+ // Find reference to the type declaration of the struct being initialized.
+ for {
+ p, ok := typ.Underlying().(*types.Pointer)
+ if !ok {
+ break
+ }
+ typ = p.Elem()
+ }
+ typ = typ.Underlying()
+
+ if typ == nil {
+ return
+ }
+
+ switch obj := typ.(type) {
+ case *types.Struct:
+ fieldCount := obj.NumFields()
+ if fieldCount == 0 {
+ return
+ }
+ var fieldSourceCode strings.Builder
+ for i := 0; i < fieldCount; i++ {
+ field := obj.Field(i)
+ // Ignore fields that are not accessible in the current package.
+ if field.Pkg() != nil && field.Pkg() != pass.Pkg && !field.Exported() {
+ continue
+ }
+
+ label := field.Name()
+ value := analysisinternal.ZeroValue(pass.Fset, file, pass.Pkg, field.Type())
+ if value == nil {
+ continue
+ }
+ var valBuf bytes.Buffer
+ if err := format.Node(&valBuf, pass.Fset, value); err != nil {
+ return
+ }
+ fieldSourceCode.WriteString("\n")
+ fieldSourceCode.WriteString(label)
+ fieldSourceCode.WriteString(" : ")
+ fieldSourceCode.WriteString(valBuf.String())
+ fieldSourceCode.WriteString(",")
+ }
+
+ if fieldSourceCode.Len() == 0 {
+ return
+ }
+
+ fieldSourceCode.WriteString("\n")
+
+ buf := []byte(fieldSourceCode.String())
+
+ pass.Report(analysis.Diagnostic{
+ Pos: expr.Lbrace,
+ End: expr.Rbrace,
+ SuggestedFixes: []analysis.SuggestedFix{{
+ Message: "Fill struct with empty values",
+ TextEdits: []analysis.TextEdit{{
+ Pos: expr.Lbrace + 1,
+ End: expr.Rbrace,
+ NewText: buf,
+ }},
+ }},
+ })
+ }
+ })
+ return nil, nil
+}
diff --git a/internal/lsp/analysis/fillstruct/fillstruct_test.go b/internal/lsp/analysis/fillstruct/fillstruct_test.go
new file mode 100644
index 0000000..cdd1bde
--- /dev/null
+++ b/internal/lsp/analysis/fillstruct/fillstruct_test.go
@@ -0,0 +1,17 @@
+// Copyright 2020 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 fillstruct_test
+
+import (
+ "testing"
+
+ "golang.org/x/tools/go/analysis/analysistest"
+ "golang.org/x/tools/internal/lsp/analysis/fillstruct"
+)
+
+func Test(t *testing.T) {
+ testdata := analysistest.TestData()
+ analysistest.RunWithSuggestedFixes(t, testdata, fillstruct.Analyzer, "a")
+}
diff --git a/internal/lsp/analysis/fillstruct/testdata/src/a/a.go b/internal/lsp/analysis/fillstruct/testdata/src/a/a.go
new file mode 100644
index 0000000..447ed15
--- /dev/null
+++ b/internal/lsp/analysis/fillstruct/testdata/src/a/a.go
@@ -0,0 +1,39 @@
+// Copyright 2020 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 fillstruct
+
+import (
+ data "b"
+)
+
+type emptyStruct struct{}
+
+var _ = emptyStruct{}
+
+type basicStruct struct {
+ foo int
+}
+
+var _ = basicStruct{} // want ""
+
+type twoArgStruct struct {
+ foo int
+ bar string
+}
+
+var _ = twoArgStruct{} // want ""
+
+var _ = twoArgStruct{
+ bar: "bar",
+}
+
+type nestedStruct struct {
+ bar string
+ basic basicStruct
+}
+
+var _ = nestedStruct{} // want ""
+
+var _ = data.B{} // want ""
diff --git a/internal/lsp/analysis/fillstruct/testdata/src/a/a.go.golden b/internal/lsp/analysis/fillstruct/testdata/src/a/a.go.golden
new file mode 100644
index 0000000..3fc564b
--- /dev/null
+++ b/internal/lsp/analysis/fillstruct/testdata/src/a/a.go.golden
@@ -0,0 +1,49 @@
+// Copyright 2020 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 fillstruct
+
+import (
+ data "b"
+)
+
+type emptyStruct struct{}
+
+var _ = emptyStruct{}
+
+type basicStruct struct {
+ foo int
+}
+
+var _ = basicStruct{
+ foo: 0,
+} // want ""
+
+type twoArgStruct struct {
+ foo int
+ bar string
+}
+
+var _ = twoArgStruct{
+ foo: 0,
+ bar: "",
+} // want ""
+
+var _ = twoArgStruct{
+ bar: "bar",
+}
+
+type nestedStruct struct {
+ bar string
+ basic basicStruct
+}
+
+var _ = nestedStruct{
+ bar: "",
+ basic: basicStruct{},
+} // want ""
+
+var _ = data.B{
+ ExportedInt: 0,
+} // want ""
diff --git a/internal/lsp/analysis/fillstruct/testdata/src/b/b.go b/internal/lsp/analysis/fillstruct/testdata/src/b/b.go
new file mode 100644
index 0000000..a4b3946
--- /dev/null
+++ b/internal/lsp/analysis/fillstruct/testdata/src/b/b.go
@@ -0,0 +1,6 @@
+package fillstruct
+
+type B struct {
+ ExportedInt int
+ unexportedInt int
+}
diff --git a/internal/lsp/source/options.go b/internal/lsp/source/options.go
index 11eaf05..13aec4c 100644
--- a/internal/lsp/source/options.go
+++ b/internal/lsp/source/options.go
@@ -38,6 +38,7 @@
"golang.org/x/tools/go/analysis/passes/unsafeptr"
"golang.org/x/tools/go/analysis/passes/unusedresult"
"golang.org/x/tools/internal/lsp/analysis/fillreturns"
+ "golang.org/x/tools/internal/lsp/analysis/fillstruct"
"golang.org/x/tools/internal/lsp/analysis/nonewvars"
"golang.org/x/tools/internal/lsp/analysis/noresultvalues"
"golang.org/x/tools/internal/lsp/analysis/simplifycompositelit"
@@ -130,11 +131,12 @@
TempModfile: true,
},
Hooks: Hooks{
- ComputeEdits: myers.ComputeEdits,
- URLRegexp: regexp.MustCompile(`(http|ftp|https)://([\w_-]+(?:(?:\.[\w_-]+)+))([\w.,@?^=%&:/~+#-]*[\w@?^=%&/~+#-])?`),
- DefaultAnalyzers: defaultAnalyzers(),
- TypeErrorAnalyzers: typeErrorAnalyzers(),
- GoDiff: true,
+ ComputeEdits: myers.ComputeEdits,
+ URLRegexp: regexp.MustCompile(`(http|ftp|https)://([\w_-]+(?:(?:\.[\w_-]+)+))([\w.,@?^=%&:/~+#-]*[\w@?^=%&/~+#-])?`),
+ DefaultAnalyzers: defaultAnalyzers(),
+ TypeErrorAnalyzers: typeErrorAnalyzers(),
+ ConvenienceAnalyzers: convenienceAnalyzers(),
+ GoDiff: true,
},
}
}
@@ -243,11 +245,12 @@
// Hooks contains configuration that is provided to the Gopls command by the
// main package.
type Hooks struct {
- GoDiff bool
- ComputeEdits diff.ComputeEdits
- URLRegexp *regexp.Regexp
- DefaultAnalyzers map[string]Analyzer
- TypeErrorAnalyzers map[string]Analyzer
+ GoDiff bool
+ ComputeEdits diff.ComputeEdits
+ URLRegexp *regexp.Regexp
+ DefaultAnalyzers map[string]Analyzer
+ TypeErrorAnalyzers map[string]Analyzer
+ ConvenienceAnalyzers map[string]Analyzer
}
func (o Options) AddDefaultAnalyzer(a *analysis.Analyzer) {
@@ -625,6 +628,15 @@
}
}
+func convenienceAnalyzers() map[string]Analyzer {
+ return map[string]Analyzer{
+ fillstruct.Analyzer.Name: {
+ Analyzer: fillstruct.Analyzer,
+ enabled: true,
+ },
+ }
+}
+
func defaultAnalyzers() map[string]Analyzer {
return map[string]Analyzer{
// The traditional vet suite:
