src/cmd/go/internal/modload/vendor.go - go - Git at Google

 // 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 modload

 import (
 	"errors"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
 	"sync"

 	"cmd/go/internal/base"

 	"golang.org/x/mod/module"
 	"golang.org/x/mod/semver"
 )

 var (
 	vendorOnce      sync.Once
 	vendorList      []module.Version          // modules that contribute packages to the build, in order of appearance
 	vendorReplaced  []module.Version          // all replaced modules; may or may not also contribute packages
 	vendorVersion   map[string]string         // module path → selected version (if known)
 	vendorPkgModule map[string]module.Version // package → containing module
 	vendorMeta      map[module.Version]vendorMetadata
 )

 type vendorMetadata struct {
 	Explicit    bool
 	Replacement module.Version
 }

 // readVendorList reads the list of vendored modules from vendor/modules.txt.
 func readVendorList() {
 	vendorOnce.Do(func() {
 		vendorList = nil
 		vendorPkgModule = make(map[string]module.Version)
 		vendorVersion = make(map[string]string)
 		vendorMeta = make(map[module.Version]vendorMetadata)
 		data, err := ioutil.ReadFile(filepath.Join(ModRoot(), "vendor/modules.txt"))
 		if err != nil {
 			if !errors.Is(err, os.ErrNotExist) {
 				base.Fatalf("go: %s", err)
 			}
 			return
 		}

 		var mod module.Version
 		for _, line := range strings.Split(string(data), "\n") {
 			if strings.HasPrefix(line, "# ") {
 				f := strings.Fields(line)

 				if len(f) < 3 {
 					continue
 				}
 				if semver.IsValid(f[2]) {
 					// A module, but we don't yet know whether it is in the build list or
 					// only included to indicate a replacement.
 					mod = module.Version{Path: f[1], Version: f[2]}
 					f = f[3:]
 				} else if f[2] == "=>" {
 					// A wildcard replacement found in the main module's go.mod file.
 					mod = module.Version{Path: f[1]}
 					f = f[2:]
 				} else {
 					// Not a version or a wildcard replacement.
 					// We don't know how to interpret this module line, so ignore it.
 					mod = module.Version{}
 					continue
 				}

 				if len(f) >= 2 && f[0] == "=>" {
 					meta := vendorMeta[mod]
 					if len(f) == 2 {
 						// File replacement.
 						meta.Replacement = module.Version{Path: f[1]}
 						vendorReplaced = append(vendorReplaced, mod)
 					} else if len(f) == 3 && semver.IsValid(f[2]) {
 						// Path and version replacement.
 						meta.Replacement = module.Version{Path: f[1], Version: f[2]}
 						vendorReplaced = append(vendorReplaced, mod)
 					} else {
 						// We don't understand this replacement. Ignore it.
 					}
 					vendorMeta[mod] = meta
 				}
 				continue
 			}

 			// Not a module line. Must be a package within a module or a metadata
 			// directive, either of which requires a preceding module line.
 			if mod.Path == "" {
 				continue
 			}

 			if strings.HasPrefix(line, "## ") {
 				// Metadata. Take the union of annotations across multiple lines, if present.
 				meta := vendorMeta[mod]
 				for _, entry := range strings.Split(strings.TrimPrefix(line, "## "), ";") {
 					entry = strings.TrimSpace(entry)
 					if entry == "explicit" {
 						meta.Explicit = true
 					}
 					// All other tokens are reserved for future use.
 				}
 				vendorMeta[mod] = meta
 				continue
 			}

 			if f := strings.Fields(line); len(f) == 1 && module.CheckImportPath(f[0]) == nil {
 				// A package within the current module.
 				vendorPkgModule[f[0]] = mod

 				// Since this module provides a package for the build, we know that it
 				// is in the build list and is the selected version of its path.
 				// If this information is new, record it.
 				if v, ok := vendorVersion[mod.Path]; !ok || semver.Compare(v, mod.Version) < 0 {
 					vendorList = append(vendorList, mod)
 					vendorVersion[mod.Path] = mod.Version
 				}
 			}
 		}
 	})
 }

 // checkVendorConsistency verifies that the vendor/modules.txt file matches (if
 // go 1.14) or at least does not contradict (go 1.13 or earlier) the
 // requirements and replacements listed in the main module's go.mod file.
 func checkVendorConsistency() {
 	readVendorList()

 	pre114 := false
 	if semver.Compare(index.goVersionV, "v1.14") < 0 {
 		// Go versions before 1.14 did not include enough information in
 		// vendor/modules.txt to check for consistency.
 		// If we know that we're on an earlier version, relax the consistency check.
 		pre114 = true
 	}

 	vendErrors := new(strings.Builder)
 	vendErrorf := func(mod module.Version, format string, args ...interface{}) {
 		detail := fmt.Sprintf(format, args...)
 		if mod.Version == "" {
 			fmt.Fprintf(vendErrors, "\n\t%s: %s", mod.Path, detail)
 		} else {
 			fmt.Fprintf(vendErrors, "\n\t%s@%s: %s", mod.Path, mod.Version, detail)
 		}
 	}

 	// Iterate over the Require directives in their original (not indexed) order
 	// so that the errors match the original file.
 	for _, r := range modFile.Require {
 		if !vendorMeta[r.Mod].Explicit {
 			if pre114 {
 				// Before 1.14, modules.txt did not indicate whether modules were listed
 				// explicitly in the main module's go.mod file.
 				// However, we can at least detect a version mismatch if packages were
 				// vendored from a non-matching version.
 				if vv, ok := vendorVersion[r.Mod.Path]; ok && vv != r.Mod.Version {
 					vendErrorf(r.Mod, fmt.Sprintf("is explicitly required in go.mod, but vendor/modules.txt indicates %s@%s", r.Mod.Path, vv))
 				}
 			} else {
 				vendErrorf(r.Mod, "is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt")
 			}
 		}
 	}

 	describe := func(m module.Version) string {
 		if m.Version == "" {
 			return m.Path
 		}
 		return m.Path + "@" + m.Version
 	}

 	// We need to verify *all* replacements that occur in modfile: even if they
 	// don't directly apply to any module in the vendor list, the replacement
 	// go.mod file can affect the selected versions of other (transitive)
 	// dependencies
 	for _, r := range modFile.Replace {
 		vr := vendorMeta[r.Old].Replacement
 		if vr == (module.Version{}) {
 			if pre114 && (r.Old.Version == "" || vendorVersion[r.Old.Path] != r.Old.Version) {
 				// Before 1.14, modules.txt omitted wildcard replacements and
 				// replacements for modules that did not have any packages to vendor.
 			} else {
 				vendErrorf(r.Old, "is replaced in go.mod, but not marked as replaced in vendor/modules.txt")
 			}
 		} else if vr != r.New {
 			vendErrorf(r.Old, "is replaced by %s in go.mod, but marked as replaced by %s in vendor/modules.txt", describe(r.New), describe(vr))
 		}
 	}

 	for _, mod := range vendorList {
 		meta := vendorMeta[mod]
 		if meta.Explicit {
 			if _, inGoMod := index.require[mod]; !inGoMod {
 				vendErrorf(mod, "is marked as explicit in vendor/modules.txt, but not explicitly required in go.mod")
 			}
 		}
 	}

 	for _, mod := range vendorReplaced {
 		r := Replacement(mod)
 		if r == (module.Version{}) {
 			vendErrorf(mod, "is marked as replaced in vendor/modules.txt, but not replaced in go.mod")
 			continue
 		}
 		if meta := vendorMeta[mod]; r != meta.Replacement {
 			vendErrorf(mod, "is marked as replaced by %s in vendor/modules.txt, but replaced by %s in go.mod", describe(meta.Replacement), describe(r))
 		}
 	}

 	if vendErrors.Len() > 0 {
 		base.Fatalf("go: inconsistent vendoring in %s:%s\n\nrun 'go mod vendor' to sync, or use -mod=mod or -mod=readonly to ignore the vendor directory", modRoot, vendErrors)
 	}
 }
	// 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 modload

	import (
	"errors"
	"fmt"
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"
	"sync"

	"cmd/go/internal/base"

	"golang.org/x/mod/module"
	"golang.org/x/mod/semver"
	)

	var (
	vendorOnce sync.Once
	vendorList []module.Version // modules that contribute packages to the build, in order of appearance
	vendorReplaced []module.Version // all replaced modules; may or may not also contribute packages
	vendorVersion map[string]string // module path → selected version (if known)
	vendorPkgModule map[string]module.Version // package → containing module
	vendorMeta map[module.Version]vendorMetadata
	)

	type vendorMetadata struct {
	Explicit bool
	Replacement module.Version
	}

	// readVendorList reads the list of vendored modules from vendor/modules.txt.
	func readVendorList() {
	vendorOnce.Do(func() {
	vendorList = nil
	vendorPkgModule = make(map[string]module.Version)
	vendorVersion = make(map[string]string)
	vendorMeta = make(map[module.Version]vendorMetadata)
	data, err := ioutil.ReadFile(filepath.Join(ModRoot(), "vendor/modules.txt"))
	if err != nil {
	if !errors.Is(err, os.ErrNotExist) {
	base.Fatalf("go: %s", err)
	}
	return
	}

	var mod module.Version
	for _, line := range strings.Split(string(data), "\n") {
	if strings.HasPrefix(line, "# ") {
	f := strings.Fields(line)

	if len(f) < 3 {
	continue
	}
	if semver.IsValid(f[2]) {
	// A module, but we don't yet know whether it is in the build list or
	// only included to indicate a replacement.
	mod = module.Version{Path: f[1], Version: f[2]}
	f = f[3:]
	} else if f[2] == "=>" {
	// A wildcard replacement found in the main module's go.mod file.
	mod = module.Version{Path: f[1]}
	f = f[2:]
	} else {
	// Not a version or a wildcard replacement.
	// We don't know how to interpret this module line, so ignore it.
	mod = module.Version{}
	continue
	}

	if len(f) >= 2 && f[0] == "=>" {
	meta := vendorMeta[mod]
	if len(f) == 2 {
	// File replacement.
	meta.Replacement = module.Version{Path: f[1]}
	vendorReplaced = append(vendorReplaced, mod)
	} else if len(f) == 3 && semver.IsValid(f[2]) {
	// Path and version replacement.
	meta.Replacement = module.Version{Path: f[1], Version: f[2]}
	vendorReplaced = append(vendorReplaced, mod)
	} else {
	// We don't understand this replacement. Ignore it.
	}
	vendorMeta[mod] = meta
	}
	continue
	}

	// Not a module line. Must be a package within a module or a metadata
	// directive, either of which requires a preceding module line.
	if mod.Path == "" {
	continue
	}

	if strings.HasPrefix(line, "## ") {
	// Metadata. Take the union of annotations across multiple lines, if present.
	meta := vendorMeta[mod]
	for _, entry := range strings.Split(strings.TrimPrefix(line, "## "), ";") {
	entry = strings.TrimSpace(entry)
	if entry == "explicit" {
	meta.Explicit = true
	}
	// All other tokens are reserved for future use.
	}
	vendorMeta[mod] = meta
	continue
	}

	if f := strings.Fields(line); len(f) == 1 && module.CheckImportPath(f[0]) == nil {
	// A package within the current module.
	vendorPkgModule[f[0]] = mod

	// Since this module provides a package for the build, we know that it
	// is in the build list and is the selected version of its path.
	// If this information is new, record it.
	if v, ok := vendorVersion[mod.Path]; !ok \|\| semver.Compare(v, mod.Version) < 0 {
	vendorList = append(vendorList, mod)
	vendorVersion[mod.Path] = mod.Version
	}
	}
	}
	})
	}

	// checkVendorConsistency verifies that the vendor/modules.txt file matches (if
	// go 1.14) or at least does not contradict (go 1.13 or earlier) the
	// requirements and replacements listed in the main module's go.mod file.
	func checkVendorConsistency() {
	readVendorList()

	pre114 := false
	if semver.Compare(index.goVersionV, "v1.14") < 0 {
	// Go versions before 1.14 did not include enough information in
	// vendor/modules.txt to check for consistency.
	// If we know that we're on an earlier version, relax the consistency check.
	pre114 = true
	}

	vendErrors := new(strings.Builder)
	vendErrorf := func(mod module.Version, format string, args ...interface{}) {
	detail := fmt.Sprintf(format, args...)
	if mod.Version == "" {
	fmt.Fprintf(vendErrors, "\n\t%s: %s", mod.Path, detail)
	} else {
	fmt.Fprintf(vendErrors, "\n\t%s@%s: %s", mod.Path, mod.Version, detail)
	}
	}

	// Iterate over the Require directives in their original (not indexed) order
	// so that the errors match the original file.
	for _, r := range modFile.Require {
	if !vendorMeta[r.Mod].Explicit {
	if pre114 {
	// Before 1.14, modules.txt did not indicate whether modules were listed
	// explicitly in the main module's go.mod file.
	// However, we can at least detect a version mismatch if packages were
	// vendored from a non-matching version.
	if vv, ok := vendorVersion[r.Mod.Path]; ok && vv != r.Mod.Version {
	vendErrorf(r.Mod, fmt.Sprintf("is explicitly required in go.mod, but vendor/modules.txt indicates %s@%s", r.Mod.Path, vv))
	}
	} else {
	vendErrorf(r.Mod, "is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt")
	}
	}
	}

	describe := func(m module.Version) string {
	if m.Version == "" {
	return m.Path
	}
	return m.Path + "@" + m.Version
	}

	// We need to verify all replacements that occur in modfile: even if they
	// don't directly apply to any module in the vendor list, the replacement
	// go.mod file can affect the selected versions of other (transitive)
	// dependencies
	for _, r := range modFile.Replace {
	vr := vendorMeta[r.Old].Replacement
	if vr == (module.Version{}) {
	if pre114 && (r.Old.Version == "" \|\| vendorVersion[r.Old.Path] != r.Old.Version) {
	// Before 1.14, modules.txt omitted wildcard replacements and
	// replacements for modules that did not have any packages to vendor.
	} else {
	vendErrorf(r.Old, "is replaced in go.mod, but not marked as replaced in vendor/modules.txt")
	}
	} else if vr != r.New {
	vendErrorf(r.Old, "is replaced by %s in go.mod, but marked as replaced by %s in vendor/modules.txt", describe(r.New), describe(vr))
	}
	}

	for _, mod := range vendorList {
	meta := vendorMeta[mod]
	if meta.Explicit {
	if _, inGoMod := index.require[mod]; !inGoMod {
	vendErrorf(mod, "is marked as explicit in vendor/modules.txt, but not explicitly required in go.mod")
	}
	}
	}

	for _, mod := range vendorReplaced {
	r := Replacement(mod)
	if r == (module.Version{}) {
	vendErrorf(mod, "is marked as replaced in vendor/modules.txt, but not replaced in go.mod")
	continue
	}
	if meta := vendorMeta[mod]; r != meta.Replacement {
	vendErrorf(mod, "is marked as replaced by %s in vendor/modules.txt, but replaced by %s in go.mod", describe(meta.Replacement), describe(r))
	}
	}

	if vendErrors.Len() > 0 {
	base.Fatalf("go: inconsistent vendoring in %s:%s\n\nrun 'go mod vendor' to sync, or use -mod=mod or -mod=readonly to ignore the vendor directory", modRoot, vendErrors)
	}
	}