Exemplo n.º 1
0
func TestBuild(t *testing.T) {
	saved := runtime.GOMAXPROCS(8) // Build is highly parallel
	defer runtime.GOMAXPROCS(saved)

	forward, reverse, errors := importgraph.Build(&build.Default)

	// Test direct edges.
	// We throw in crypto/hmac to prove that external test files
	// (such as this one) are inspected.
	for _, p := range []string{"go/build", "runtime", "testing", "crypto/hmac"} {
		if !forward[this][p] {
			t.Errorf("forward[importgraph][%s] not found", p)
		}
		if !reverse[p][this] {
			t.Errorf("reverse[%s][importgraph] not found", p)
		}
	}

	// Test non-existent direct edges
	for _, p := range []string{"fmt", "errors", "reflect"} {
		if forward[this][p] {
			t.Errorf("unexpected: forward[importgraph][%s] found", p)
		}
		if reverse[p][this] {
			t.Errorf("unexpected: reverse[%s][importgraph] found", p)
		}
	}

	// Test Search is reflexive.
	if !forward.Search(this)[this] {
		t.Errorf("irreflexive: forward.Search(importgraph)[importgraph] not found")
	}
	if !reverse.Search(this)[this] {
		t.Errorf("irrefexive: reverse.Search(importgraph)[importgraph] not found")
	}

	// Test Search is transitive.  (There is no direct edge to these packages.)
	for _, p := range []string{"errors", "reflect", "unsafe"} {
		if !forward.Search(this)[p] {
			t.Errorf("intransitive: forward.Search(importgraph)[%s] not found", p)
		}
		if !reverse.Search(p)[this] {
			t.Errorf("intransitive: reverse.Search(%s)[importgraph] not found", p)
		}
	}

	// Test strongly-connected components.  Because A's external
	// test package can depend on B, and vice versa, most of the
	// standard libraries are mutually dependent when their external
	// tests are considered.
	//
	// For any nodes x, y in the same SCC, y appears in the results
	// of both forward and reverse searches starting from x
	if !forward.Search("fmt")["io"] ||
		!forward.Search("io")["fmt"] ||
		!reverse.Search("fmt")["io"] ||
		!reverse.Search("io")["fmt"] {
		t.Errorf("fmt and io are not mutually reachable despite being in the same SCC")
	}

	// debugging
	if false {
		for path, err := range errors {
			t.Logf("%s: %s", path, err)
		}
		printSorted := func(direction string, g importgraph.Graph, start string) {
			t.Log(direction)
			var pkgs []string
			for pkg := range g.Search(start) {
				pkgs = append(pkgs, pkg)
			}
			sort.Strings(pkgs)
			for _, pkg := range pkgs {
				t.Logf("\t%s", pkg)
			}
		}
		printSorted("forward", forward, this)
		printSorted("reverse", reverse, this)
	}
}
Exemplo n.º 2
0
func Main(ctxt *build.Context, offsetFlag, fromFlag, to string) error {
	// -- Parse the -from or -offset specifier ----------------------------

	if (offsetFlag == "") == (fromFlag == "") {
		return fmt.Errorf("exactly one of the -from and -offset flags must be specified")
	}

	if !isValidIdentifier(to) {
		return fmt.Errorf("-to %q: not a valid identifier", to)
	}

	var spec *spec
	var err error
	if fromFlag != "" {
		spec, err = parseFromFlag(ctxt, fromFlag)
	} else {
		spec, err = parseOffsetFlag(ctxt, offsetFlag)
	}
	if err != nil {
		return err
	}

	if spec.fromName == to {
		return fmt.Errorf("the old and new names are the same: %s", to)
	}

	// -- Load the program consisting of the initial package  -------------

	iprog, err := loadProgram(ctxt, map[string]bool{spec.pkg: true})
	if err != nil {
		return err
	}

	fromObjects, err := findFromObjects(iprog, spec)
	if err != nil {
		return err
	}

	// -- Load a larger program, for global renamings ---------------------

	if requiresGlobalRename(fromObjects, to) {
		// For a local refactoring, we needn't load more
		// packages, but if the renaming affects the package's
		// API, we we must load all packages that depend on the
		// package defining the object, plus their tests.

		if Verbose {
			fmt.Fprintln(os.Stderr, "Potentially global renaming; scanning workspace...")
		}

		// Scan the workspace and build the import graph.
		_, rev, errors := importgraph.Build(ctxt)
		if len(errors) > 0 {
			fmt.Fprintf(os.Stderr, "While scanning Go workspace:\n")
			for path, err := range errors {
				fmt.Fprintf(os.Stderr, "Package %q: %s.\n", path, err)
			}
		}

		// Enumerate the set of potentially affected packages.
		affectedPackages := make(map[string]bool)
		for _, obj := range fromObjects {
			// External test packages are never imported,
			// so they will never appear in the graph.
			for path := range rev.Search(obj.Pkg().Path()) {
				affectedPackages[path] = true
			}
		}

		// TODO(adonovan): allow the user to specify the scope,
		// or -ignore patterns?  Computing the scope when we
		// don't (yet) support inputs containing errors can make
		// the tool rather brittle.

		// Re-load the larger program.
		iprog, err = loadProgram(ctxt, affectedPackages)
		if err != nil {
			return err
		}

		fromObjects, err = findFromObjects(iprog, spec)
		if err != nil {
			return err
		}
	}

	// -- Do the renaming -------------------------------------------------

	r := renamer{
		iprog:        iprog,
		objsToUpdate: make(map[types.Object]bool),
		to:           to,
		packages:     make(map[*types.Package]*loader.PackageInfo),
	}

	// Only the initially imported packages (iprog.Imported) and
	// their external tests (iprog.Created) should be inspected or
	// modified, as only they have type-checked functions bodies.
	// The rest are just dependencies, needed only for package-level
	// type information.
	for _, info := range iprog.Imported {
		r.packages[info.Pkg] = info
	}
	for _, info := range iprog.Created { // (tests)
		r.packages[info.Pkg] = info
	}

	for _, from := range fromObjects {
		r.check(from)
	}
	if r.hadConflicts && !Force {
		return ConflictError
	}
	if DryRun {
		// TODO(adonovan): print the delta?
		return nil
	}
	return r.update()
}