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)
}
}
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()
}
