func()

in go/packages/golist_overlay.go [27:260]


func (state *golistState) processGolistOverlay(response *responseDeduper) (modifiedPkgs, needPkgs []string, err error) {
	havePkgs := make(map[string]string) // importPath -> non-test package ID
	needPkgsSet := make(map[string]bool)
	modifiedPkgsSet := make(map[string]bool)

	pkgOfDir := make(map[string][]*Package)
	for _, pkg := range response.dr.Packages {
		// This is an approximation of import path to id. This can be
		// wrong for tests, vendored packages, and a number of other cases.
		havePkgs[pkg.PkgPath] = pkg.ID
		dir, err := commonDir(pkg.GoFiles)
		if err != nil {
			return nil, nil, err
		}
		if dir != "" {
			pkgOfDir[dir] = append(pkgOfDir[dir], pkg)
		}
	}

	// If no new imports are added, it is safe to avoid loading any needPkgs.
	// Otherwise, it's hard to tell which package is actually being loaded
	// (due to vendoring) and whether any modified package will show up
	// in the transitive set of dependencies (because new imports are added,
	// potentially modifying the transitive set of dependencies).
	var overlayAddsImports bool

	// If both a package and its test package are created by the overlay, we
	// need the real package first. Process all non-test files before test
	// files, and make the whole process deterministic while we're at it.
	var overlayFiles []string
	for opath := range state.cfg.Overlay {
		overlayFiles = append(overlayFiles, opath)
	}
	sort.Slice(overlayFiles, func(i, j int) bool {
		iTest := strings.HasSuffix(overlayFiles[i], "_test.go")
		jTest := strings.HasSuffix(overlayFiles[j], "_test.go")
		if iTest != jTest {
			return !iTest // non-tests are before tests.
		}
		return overlayFiles[i] < overlayFiles[j]
	})
	for _, opath := range overlayFiles {
		contents := state.cfg.Overlay[opath]
		base := filepath.Base(opath)
		dir := filepath.Dir(opath)
		var pkg *Package           // if opath belongs to both a package and its test variant, this will be the test variant
		var testVariantOf *Package // if opath is a test file, this is the package it is testing
		var fileExists bool
		isTestFile := strings.HasSuffix(opath, "_test.go")
		pkgName, ok := extractPackageName(opath, contents)
		if !ok {
			// Don't bother adding a file that doesn't even have a parsable package statement
			// to the overlay.
			continue
		}
		// If all the overlay files belong to a different package, change the
		// package name to that package.
		maybeFixPackageName(pkgName, isTestFile, pkgOfDir[dir])
	nextPackage:
		for _, p := range response.dr.Packages {
			if pkgName != p.Name && p.ID != "command-line-arguments" {
				continue
			}
			for _, f := range p.GoFiles {
				if !sameFile(filepath.Dir(f), dir) {
					continue
				}
				// Make sure to capture information on the package's test variant, if needed.
				if isTestFile && !hasTestFiles(p) {
					// TODO(matloob): Are there packages other than the 'production' variant
					// of a package that this can match? This shouldn't match the test main package
					// because the file is generated in another directory.
					testVariantOf = p
					continue nextPackage
				} else if !isTestFile && hasTestFiles(p) {
					// We're examining a test variant, but the overlaid file is
					// a non-test file. Because the overlay implementation
					// (currently) only adds a file to one package, skip this
					// package, so that we can add the file to the production
					// variant of the package. (https://golang.org/issue/36857
					// tracks handling overlays on both the production and test
					// variant of a package).
					continue nextPackage
				}
				if pkg != nil && p != pkg && pkg.PkgPath == p.PkgPath {
					// We have already seen the production version of the
					// for which p is a test variant.
					if hasTestFiles(p) {
						testVariantOf = pkg
					}
				}
				pkg = p
				if filepath.Base(f) == base {
					fileExists = true
				}
			}
		}
		// The overlay could have included an entirely new package or an
		// ad-hoc package. An ad-hoc package is one that we have manually
		// constructed from inadequate `go list` results for a file= query.
		// It will have the ID command-line-arguments.
		if pkg == nil || pkg.ID == "command-line-arguments" {
			// Try to find the module or gopath dir the file is contained in.
			// Then for modules, add the module opath to the beginning.
			pkgPath, ok, err := state.getPkgPath(dir)
			if err != nil {
				return nil, nil, err
			}
			if !ok {
				break
			}
			var forTest string // only set for x tests
			isXTest := strings.HasSuffix(pkgName, "_test")
			if isXTest {
				forTest = pkgPath
				pkgPath += "_test"
			}
			id := pkgPath
			if isTestFile {
				if isXTest {
					id = fmt.Sprintf("%s [%s.test]", pkgPath, forTest)
				} else {
					id = fmt.Sprintf("%s [%s.test]", pkgPath, pkgPath)
				}
			}
			if pkg != nil {
				// TODO(rstambler): We should change the package's path and ID
				// here. The only issue is that this messes with the roots.
			} else {
				// Try to reclaim a package with the same ID, if it exists in the response.
				for _, p := range response.dr.Packages {
					if reclaimPackage(p, id, opath, contents) {
						pkg = p
						break
					}
				}
				// Otherwise, create a new package.
				if pkg == nil {
					pkg = &Package{
						PkgPath: pkgPath,
						ID:      id,
						Name:    pkgName,
						Imports: make(map[string]*Package),
					}
					response.addPackage(pkg)
					havePkgs[pkg.PkgPath] = id
					// Add the production package's sources for a test variant.
					if isTestFile && !isXTest && testVariantOf != nil {
						pkg.GoFiles = append(pkg.GoFiles, testVariantOf.GoFiles...)
						pkg.CompiledGoFiles = append(pkg.CompiledGoFiles, testVariantOf.CompiledGoFiles...)
						// Add the package under test and its imports to the test variant.
						pkg.forTest = testVariantOf.PkgPath
						for k, v := range testVariantOf.Imports {
							pkg.Imports[k] = &Package{ID: v.ID}
						}
					}
					if isXTest {
						pkg.forTest = forTest
					}
				}
			}
		}
		if !fileExists {
			pkg.GoFiles = append(pkg.GoFiles, opath)
			// TODO(matloob): Adding the file to CompiledGoFiles can exhibit the wrong behavior
			// if the file will be ignored due to its build tags.
			pkg.CompiledGoFiles = append(pkg.CompiledGoFiles, opath)
			modifiedPkgsSet[pkg.ID] = true
		}
		imports, err := extractImports(opath, contents)
		if err != nil {
			// Let the parser or type checker report errors later.
			continue
		}
		for _, imp := range imports {
			// TODO(rstambler): If the package is an x test and the import has
			// a test variant, make sure to replace it.
			if _, found := pkg.Imports[imp]; found {
				continue
			}
			overlayAddsImports = true
			id, ok := havePkgs[imp]
			if !ok {
				var err error
				id, err = state.resolveImport(dir, imp)
				if err != nil {
					return nil, nil, err
				}
			}
			pkg.Imports[imp] = &Package{ID: id}
			// Add dependencies to the non-test variant version of this package as well.
			if testVariantOf != nil {
				testVariantOf.Imports[imp] = &Package{ID: id}
			}
		}
	}

	// toPkgPath guesses the package path given the id.
	toPkgPath := func(sourceDir, id string) (string, error) {
		if i := strings.IndexByte(id, ' '); i >= 0 {
			return state.resolveImport(sourceDir, id[:i])
		}
		return state.resolveImport(sourceDir, id)
	}

	// Now that new packages have been created, do another pass to determine
	// the new set of missing packages.
	for _, pkg := range response.dr.Packages {
		for _, imp := range pkg.Imports {
			if len(pkg.GoFiles) == 0 {
				return nil, nil, fmt.Errorf("cannot resolve imports for package %q with no Go files", pkg.PkgPath)
			}
			pkgPath, err := toPkgPath(filepath.Dir(pkg.GoFiles[0]), imp.ID)
			if err != nil {
				return nil, nil, err
			}
			if _, ok := havePkgs[pkgPath]; !ok {
				needPkgsSet[pkgPath] = true
			}
		}
	}

	if overlayAddsImports {
		needPkgs = make([]string, 0, len(needPkgsSet))
		for pkg := range needPkgsSet {
			needPkgs = append(needPkgs, pkg)
		}
	}
	modifiedPkgs = make([]string, 0, len(modifiedPkgsSet))
	for pkg := range modifiedPkgsSet {
		modifiedPkgs = append(modifiedPkgs, pkg)
	}
	return modifiedPkgs, needPkgs, err
}