--- /dev/null
+// Copyright 2018 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 packages
+
+// See doc.go for package documentation and implementation notes.
+
+import (
+ "context"
+ "encoding/json"
+ "fmt"
+ "go/ast"
+ "go/parser"
+ "go/scanner"
+ "go/token"
+ "go/types"
+ "io/ioutil"
+ "log"
+ "os"
+ "path/filepath"
+ "strings"
+ "sync"
+ "time"
+
+ "golang.org/x/tools/go/gcexportdata"
+ "golang.org/x/tools/internal/gocommand"
+ "golang.org/x/tools/internal/packagesinternal"
+ "golang.org/x/tools/internal/typesinternal"
+)
+
+// A LoadMode controls the amount of detail to return when loading.
+// The bits below can be combined to specify which fields should be
+// filled in the result packages.
+// The zero value is a special case, equivalent to combining
+// the NeedName, NeedFiles, and NeedCompiledGoFiles bits.
+// ID and Errors (if present) will always be filled.
+// Load may return more information than requested.
+type LoadMode int
+
+// TODO(matloob): When a V2 of go/packages is released, rename NeedExportsFile to
+// NeedExportFile to make it consistent with the Package field it's adding.
+
+const (
+ // NeedName adds Name and PkgPath.
+ NeedName LoadMode = 1 << iota
+
+ // NeedFiles adds GoFiles and OtherFiles.
+ NeedFiles
+
+ // NeedCompiledGoFiles adds CompiledGoFiles.
+ NeedCompiledGoFiles
+
+ // NeedImports adds Imports. If NeedDeps is not set, the Imports field will contain
+ // "placeholder" Packages with only the ID set.
+ NeedImports
+
+ // NeedDeps adds the fields requested by the LoadMode in the packages in Imports.
+ NeedDeps
+
+ // NeedExportsFile adds ExportFile.
+ NeedExportsFile
+
+ // NeedTypes adds Types, Fset, and IllTyped.
+ NeedTypes
+
+ // NeedSyntax adds Syntax.
+ NeedSyntax
+
+ // NeedTypesInfo adds TypesInfo.
+ NeedTypesInfo
+
+ // NeedTypesSizes adds TypesSizes.
+ NeedTypesSizes
+
+ // typecheckCgo enables full support for type checking cgo. Requires Go 1.15+.
+ // Modifies CompiledGoFiles and Types, and has no effect on its own.
+ typecheckCgo
+
+ // NeedModule adds Module.
+ NeedModule
+)
+
+const (
+ // Deprecated: LoadFiles exists for historical compatibility
+ // and should not be used. Please directly specify the needed fields using the Need values.
+ LoadFiles = NeedName | NeedFiles | NeedCompiledGoFiles
+
+ // Deprecated: LoadImports exists for historical compatibility
+ // and should not be used. Please directly specify the needed fields using the Need values.
+ LoadImports = LoadFiles | NeedImports
+
+ // Deprecated: LoadTypes exists for historical compatibility
+ // and should not be used. Please directly specify the needed fields using the Need values.
+ LoadTypes = LoadImports | NeedTypes | NeedTypesSizes
+
+ // Deprecated: LoadSyntax exists for historical compatibility
+ // and should not be used. Please directly specify the needed fields using the Need values.
+ LoadSyntax = LoadTypes | NeedSyntax | NeedTypesInfo
+
+ // Deprecated: LoadAllSyntax exists for historical compatibility
+ // and should not be used. Please directly specify the needed fields using the Need values.
+ LoadAllSyntax = LoadSyntax | NeedDeps
+)
+
+// A Config specifies details about how packages should be loaded.
+// The zero value is a valid configuration.
+// Calls to Load do not modify this struct.
+type Config struct {
+ // Mode controls the level of information returned for each package.
+ Mode LoadMode
+
+ // Context specifies the context for the load operation.
+ // If the context is cancelled, the loader may stop early
+ // and return an ErrCancelled error.
+ // If Context is nil, the load cannot be cancelled.
+ Context context.Context
+
+ // Logf is the logger for the config.
+ // If the user provides a logger, debug logging is enabled.
+ // If the GOPACKAGESDEBUG environment variable is set to true,
+ // but the logger is nil, default to log.Printf.
+ Logf func(format string, args ...interface{})
+
+ // Dir is the directory in which to run the build system's query tool
+ // that provides information about the packages.
+ // If Dir is empty, the tool is run in the current directory.
+ Dir string
+
+ // Env is the environment to use when invoking the build system's query tool.
+ // If Env is nil, the current environment is used.
+ // As in os/exec's Cmd, only the last value in the slice for
+ // each environment key is used. To specify the setting of only
+ // a few variables, append to the current environment, as in:
+ //
+ // opt.Env = append(os.Environ(), "GOOS=plan9", "GOARCH=386")
+ //
+ Env []string
+
+ // gocmdRunner guards go command calls from concurrency errors.
+ gocmdRunner *gocommand.Runner
+
+ // BuildFlags is a list of command-line flags to be passed through to
+ // the build system's query tool.
+ BuildFlags []string
+
+ // modFile will be used for -modfile in go command invocations.
+ modFile string
+
+ // modFlag will be used for -modfile in go command invocations.
+ modFlag string
+
+ // Fset provides source position information for syntax trees and types.
+ // If Fset is nil, Load will use a new fileset, but preserve Fset's value.
+ Fset *token.FileSet
+
+ // ParseFile is called to read and parse each file
+ // when preparing a package's type-checked syntax tree.
+ // It must be safe to call ParseFile simultaneously from multiple goroutines.
+ // If ParseFile is nil, the loader will uses parser.ParseFile.
+ //
+ // ParseFile should parse the source from src and use filename only for
+ // recording position information.
+ //
+ // An application may supply a custom implementation of ParseFile
+ // to change the effective file contents or the behavior of the parser,
+ // or to modify the syntax tree. For example, selectively eliminating
+ // unwanted function bodies can significantly accelerate type checking.
+ ParseFile func(fset *token.FileSet, filename string, src []byte) (*ast.File, error)
+
+ // If Tests is set, the loader includes not just the packages
+ // matching a particular pattern but also any related test packages,
+ // including test-only variants of the package and the test executable.
+ //
+ // For example, when using the go command, loading "fmt" with Tests=true
+ // returns four packages, with IDs "fmt" (the standard package),
+ // "fmt [fmt.test]" (the package as compiled for the test),
+ // "fmt_test" (the test functions from source files in package fmt_test),
+ // and "fmt.test" (the test binary).
+ //
+ // In build systems with explicit names for tests,
+ // setting Tests may have no effect.
+ Tests bool
+
+ // Overlay provides a mapping of absolute file paths to file contents.
+ // If the file with the given path already exists, the parser will use the
+ // alternative file contents provided by the map.
+ //
+ // Overlays provide incomplete support for when a given file doesn't
+ // already exist on disk. See the package doc above for more details.
+ Overlay map[string][]byte
+}
+
+// driver is the type for functions that query the build system for the
+// packages named by the patterns.
+type driver func(cfg *Config, patterns ...string) (*driverResponse, error)
+
+// driverResponse contains the results for a driver query.
+type driverResponse struct {
+ // NotHandled is returned if the request can't be handled by the current
+ // driver. If an external driver returns a response with NotHandled, the
+ // rest of the driverResponse is ignored, and go/packages will fallback
+ // to the next driver. If go/packages is extended in the future to support
+ // lists of multiple drivers, go/packages will fall back to the next driver.
+ NotHandled bool
+
+ // Sizes, if not nil, is the types.Sizes to use when type checking.
+ Sizes *types.StdSizes
+
+ // Roots is the set of package IDs that make up the root packages.
+ // We have to encode this separately because when we encode a single package
+ // we cannot know if it is one of the roots as that requires knowledge of the
+ // graph it is part of.
+ Roots []string `json:",omitempty"`
+
+ // Packages is the full set of packages in the graph.
+ // The packages are not connected into a graph.
+ // The Imports if populated will be stubs that only have their ID set.
+ // Imports will be connected and then type and syntax information added in a
+ // later pass (see refine).
+ Packages []*Package
+}
+
+// Load loads and returns the Go packages named by the given patterns.
+//
+// Config specifies loading options;
+// nil behaves the same as an empty Config.
+//
+// Load returns an error if any of the patterns was invalid
+// as defined by the underlying build system.
+// It may return an empty list of packages without an error,
+// for instance for an empty expansion of a valid wildcard.
+// Errors associated with a particular package are recorded in the
+// corresponding Package's Errors list, and do not cause Load to
+// return an error. Clients may need to handle such errors before
+// proceeding with further analysis. The PrintErrors function is
+// provided for convenient display of all errors.
+func Load(cfg *Config, patterns ...string) ([]*Package, error) {
+ l := newLoader(cfg)
+ response, err := defaultDriver(&l.Config, patterns...)
+ if err != nil {
+ return nil, err
+ }
+ l.sizes = response.Sizes
+ return l.refine(response.Roots, response.Packages...)
+}
+
+// defaultDriver is a driver that implements go/packages' fallback behavior.
+// It will try to request to an external driver, if one exists. If there's
+// no external driver, or the driver returns a response with NotHandled set,
+// defaultDriver will fall back to the go list driver.
+func defaultDriver(cfg *Config, patterns ...string) (*driverResponse, error) {
+ driver := findExternalDriver(cfg)
+ if driver == nil {
+ driver = goListDriver
+ }
+ response, err := driver(cfg, patterns...)
+ if err != nil {
+ return response, err
+ } else if response.NotHandled {
+ return goListDriver(cfg, patterns...)
+ }
+ return response, nil
+}
+
+// A Package describes a loaded Go package.
+type Package struct {
+ // ID is a unique identifier for a package,
+ // in a syntax provided by the underlying build system.
+ //
+ // Because the syntax varies based on the build system,
+ // clients should treat IDs as opaque and not attempt to
+ // interpret them.
+ ID string
+
+ // Name is the package name as it appears in the package source code.
+ Name string
+
+ // PkgPath is the package path as used by the go/types package.
+ PkgPath string
+
+ // Errors contains any errors encountered querying the metadata
+ // of the package, or while parsing or type-checking its files.
+ Errors []Error
+
+ // GoFiles lists the absolute file paths of the package's Go source files.
+ GoFiles []string
+
+ // CompiledGoFiles lists the absolute file paths of the package's source
+ // files that are suitable for type checking.
+ // This may differ from GoFiles if files are processed before compilation.
+ CompiledGoFiles []string
+
+ // OtherFiles lists the absolute file paths of the package's non-Go source files,
+ // including assembly, C, C++, Fortran, Objective-C, SWIG, and so on.
+ OtherFiles []string
+
+ // IgnoredFiles lists source files that are not part of the package
+ // using the current build configuration but that might be part of
+ // the package using other build configurations.
+ IgnoredFiles []string
+
+ // ExportFile is the absolute path to a file containing type
+ // information for the package as provided by the build system.
+ ExportFile string
+
+ // Imports maps import paths appearing in the package's Go source files
+ // to corresponding loaded Packages.
+ Imports map[string]*Package
+
+ // Types provides type information for the package.
+ // The NeedTypes LoadMode bit sets this field for packages matching the
+ // patterns; type information for dependencies may be missing or incomplete,
+ // unless NeedDeps and NeedImports are also set.
+ Types *types.Package
+
+ // Fset provides position information for Types, TypesInfo, and Syntax.
+ // It is set only when Types is set.
+ Fset *token.FileSet
+
+ // IllTyped indicates whether the package or any dependency contains errors.
+ // It is set only when Types is set.
+ IllTyped bool
+
+ // Syntax is the package's syntax trees, for the files listed in CompiledGoFiles.
+ //
+ // The NeedSyntax LoadMode bit populates this field for packages matching the patterns.
+ // If NeedDeps and NeedImports are also set, this field will also be populated
+ // for dependencies.
+ Syntax []*ast.File
+
+ // TypesInfo provides type information about the package's syntax trees.
+ // It is set only when Syntax is set.
+ TypesInfo *types.Info
+
+ // TypesSizes provides the effective size function for types in TypesInfo.
+ TypesSizes types.Sizes
+
+ // forTest is the package under test, if any.
+ forTest string
+
+ // module is the module information for the package if it exists.
+ Module *Module
+}
+
+// Module provides module information for a package.
+type Module struct {
+ Path string // module path
+ Version string // module version
+ Replace *Module // replaced by this module
+ Time *time.Time // time version was created
+ Main bool // is this the main module?
+ Indirect bool // is this module only an indirect dependency of main module?
+ Dir string // directory holding files for this module, if any
+ GoMod string // path to go.mod file used when loading this module, if any
+ GoVersion string // go version used in module
+ Error *ModuleError // error loading module
+}
+
+// ModuleError holds errors loading a module.
+type ModuleError struct {
+ Err string // the error itself
+}
+
+func init() {
+ packagesinternal.GetForTest = func(p interface{}) string {
+ return p.(*Package).forTest
+ }
+ packagesinternal.GetGoCmdRunner = func(config interface{}) *gocommand.Runner {
+ return config.(*Config).gocmdRunner
+ }
+ packagesinternal.SetGoCmdRunner = func(config interface{}, runner *gocommand.Runner) {
+ config.(*Config).gocmdRunner = runner
+ }
+ packagesinternal.SetModFile = func(config interface{}, value string) {
+ config.(*Config).modFile = value
+ }
+ packagesinternal.SetModFlag = func(config interface{}, value string) {
+ config.(*Config).modFlag = value
+ }
+ packagesinternal.TypecheckCgo = int(typecheckCgo)
+}
+
+// An Error describes a problem with a package's metadata, syntax, or types.
+type Error struct {
+ Pos string // "file:line:col" or "file:line" or "" or "-"
+ Msg string
+ Kind ErrorKind
+}
+
+// ErrorKind describes the source of the error, allowing the user to
+// differentiate between errors generated by the driver, the parser, or the
+// type-checker.
+type ErrorKind int
+
+const (
+ UnknownError ErrorKind = iota
+ ListError
+ ParseError
+ TypeError
+)
+
+func (err Error) Error() string {
+ pos := err.Pos
+ if pos == "" {
+ pos = "-" // like token.Position{}.String()
+ }
+ return pos + ": " + err.Msg
+}
+
+// flatPackage is the JSON form of Package
+// It drops all the type and syntax fields, and transforms the Imports
+//
+// TODO(adonovan): identify this struct with Package, effectively
+// publishing the JSON protocol.
+type flatPackage struct {
+ ID string
+ Name string `json:",omitempty"`
+ PkgPath string `json:",omitempty"`
+ Errors []Error `json:",omitempty"`
+ GoFiles []string `json:",omitempty"`
+ CompiledGoFiles []string `json:",omitempty"`
+ OtherFiles []string `json:",omitempty"`
+ IgnoredFiles []string `json:",omitempty"`
+ ExportFile string `json:",omitempty"`
+ Imports map[string]string `json:",omitempty"`
+}
+
+// MarshalJSON returns the Package in its JSON form.
+// For the most part, the structure fields are written out unmodified, and
+// the type and syntax fields are skipped.
+// The imports are written out as just a map of path to package id.
+// The errors are written using a custom type that tries to preserve the
+// structure of error types we know about.
+//
+// This method exists to enable support for additional build systems. It is
+// not intended for use by clients of the API and we may change the format.
+func (p *Package) MarshalJSON() ([]byte, error) {
+ flat := &flatPackage{
+ ID: p.ID,
+ Name: p.Name,
+ PkgPath: p.PkgPath,
+ Errors: p.Errors,
+ GoFiles: p.GoFiles,
+ CompiledGoFiles: p.CompiledGoFiles,
+ OtherFiles: p.OtherFiles,
+ IgnoredFiles: p.IgnoredFiles,
+ ExportFile: p.ExportFile,
+ }
+ if len(p.Imports) > 0 {
+ flat.Imports = make(map[string]string, len(p.Imports))
+ for path, ipkg := range p.Imports {
+ flat.Imports[path] = ipkg.ID
+ }
+ }
+ return json.Marshal(flat)
+}
+
+// UnmarshalJSON reads in a Package from its JSON format.
+// See MarshalJSON for details about the format accepted.
+func (p *Package) UnmarshalJSON(b []byte) error {
+ flat := &flatPackage{}
+ if err := json.Unmarshal(b, &flat); err != nil {
+ return err
+ }
+ *p = Package{
+ ID: flat.ID,
+ Name: flat.Name,
+ PkgPath: flat.PkgPath,
+ Errors: flat.Errors,
+ GoFiles: flat.GoFiles,
+ CompiledGoFiles: flat.CompiledGoFiles,
+ OtherFiles: flat.OtherFiles,
+ ExportFile: flat.ExportFile,
+ }
+ if len(flat.Imports) > 0 {
+ p.Imports = make(map[string]*Package, len(flat.Imports))
+ for path, id := range flat.Imports {
+ p.Imports[path] = &Package{ID: id}
+ }
+ }
+ return nil
+}
+
+func (p *Package) String() string { return p.ID }
+
+// loaderPackage augments Package with state used during the loading phase
+type loaderPackage struct {
+ *Package
+ importErrors map[string]error // maps each bad import to its error
+ loadOnce sync.Once
+ color uint8 // for cycle detection
+ needsrc bool // load from source (Mode >= LoadTypes)
+ needtypes bool // type information is either requested or depended on
+ initial bool // package was matched by a pattern
+}
+
+// loader holds the working state of a single call to load.
+type loader struct {
+ pkgs map[string]*loaderPackage
+ Config
+ sizes types.Sizes
+ parseCache map[string]*parseValue
+ parseCacheMu sync.Mutex
+ exportMu sync.Mutex // enforces mutual exclusion of exportdata operations
+
+ // Config.Mode contains the implied mode (see impliedLoadMode).
+ // Implied mode contains all the fields we need the data for.
+ // In requestedMode there are the actually requested fields.
+ // We'll zero them out before returning packages to the user.
+ // This makes it easier for us to get the conditions where
+ // we need certain modes right.
+ requestedMode LoadMode
+}
+
+type parseValue struct {
+ f *ast.File
+ err error
+ ready chan struct{}
+}
+
+func newLoader(cfg *Config) *loader {
+ ld := &loader{
+ parseCache: map[string]*parseValue{},
+ }
+ if cfg != nil {
+ ld.Config = *cfg
+ // If the user has provided a logger, use it.
+ ld.Config.Logf = cfg.Logf
+ }
+ if ld.Config.Logf == nil {
+ // If the GOPACKAGESDEBUG environment variable is set to true,
+ // but the user has not provided a logger, default to log.Printf.
+ if debug {
+ ld.Config.Logf = log.Printf
+ } else {
+ ld.Config.Logf = func(format string, args ...interface{}) {}
+ }
+ }
+ if ld.Config.Mode == 0 {
+ ld.Config.Mode = NeedName | NeedFiles | NeedCompiledGoFiles // Preserve zero behavior of Mode for backwards compatibility.
+ }
+ if ld.Config.Env == nil {
+ ld.Config.Env = os.Environ()
+ }
+ if ld.Config.gocmdRunner == nil {
+ ld.Config.gocmdRunner = &gocommand.Runner{}
+ }
+ if ld.Context == nil {
+ ld.Context = context.Background()
+ }
+ if ld.Dir == "" {
+ if dir, err := os.Getwd(); err == nil {
+ ld.Dir = dir
+ }
+ }
+
+ // Save the actually requested fields. We'll zero them out before returning packages to the user.
+ ld.requestedMode = ld.Mode
+ ld.Mode = impliedLoadMode(ld.Mode)
+
+ if ld.Mode&NeedTypes != 0 || ld.Mode&NeedSyntax != 0 {
+ if ld.Fset == nil {
+ ld.Fset = token.NewFileSet()
+ }
+
+ // ParseFile is required even in LoadTypes mode
+ // because we load source if export data is missing.
+ if ld.ParseFile == nil {
+ ld.ParseFile = func(fset *token.FileSet, filename string, src []byte) (*ast.File, error) {
+ const mode = parser.AllErrors | parser.ParseComments
+ return parser.ParseFile(fset, filename, src, mode)
+ }
+ }
+ }
+
+ return ld
+}
+
+// refine connects the supplied packages into a graph and then adds type and
+// and syntax information as requested by the LoadMode.
+func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
+ rootMap := make(map[string]int, len(roots))
+ for i, root := range roots {
+ rootMap[root] = i
+ }
+ ld.pkgs = make(map[string]*loaderPackage)
+ // first pass, fixup and build the map and roots
+ var initial = make([]*loaderPackage, len(roots))
+ for _, pkg := range list {
+ rootIndex := -1
+ if i, found := rootMap[pkg.ID]; found {
+ rootIndex = i
+ }
+
+ // Overlays can invalidate export data.
+ // TODO(matloob): make this check fine-grained based on dependencies on overlaid files
+ exportDataInvalid := len(ld.Overlay) > 0 || pkg.ExportFile == "" && pkg.PkgPath != "unsafe"
+ // This package needs type information if the caller requested types and the package is
+ // either a root, or it's a non-root and the user requested dependencies ...
+ needtypes := (ld.Mode&NeedTypes|NeedTypesInfo != 0 && (rootIndex >= 0 || ld.Mode&NeedDeps != 0))
+ // This package needs source if the call requested source (or types info, which implies source)
+ // and the package is either a root, or itas a non- root and the user requested dependencies...
+ needsrc := ((ld.Mode&(NeedSyntax|NeedTypesInfo) != 0 && (rootIndex >= 0 || ld.Mode&NeedDeps != 0)) ||
+ // ... or if we need types and the exportData is invalid. We fall back to (incompletely)
+ // typechecking packages from source if they fail to compile.
+ (ld.Mode&NeedTypes|NeedTypesInfo != 0 && exportDataInvalid)) && pkg.PkgPath != "unsafe"
+ lpkg := &loaderPackage{
+ Package: pkg,
+ needtypes: needtypes,
+ needsrc: needsrc,
+ }
+ ld.pkgs[lpkg.ID] = lpkg
+ if rootIndex >= 0 {
+ initial[rootIndex] = lpkg
+ lpkg.initial = true
+ }
+ }
+ for i, root := range roots {
+ if initial[i] == nil {
+ return nil, fmt.Errorf("root package %v is missing", root)
+ }
+ }
+
+ // Materialize the import graph.
+
+ const (
+ white = 0 // new
+ grey = 1 // in progress
+ black = 2 // complete
+ )
+
+ // visit traverses the import graph, depth-first,
+ // and materializes the graph as Packages.Imports.
+ //
+ // Valid imports are saved in the Packages.Import map.
+ // Invalid imports (cycles and missing nodes) are saved in the importErrors map.
+ // Thus, even in the presence of both kinds of errors, the Import graph remains a DAG.
+ //
+ // visit returns whether the package needs src or has a transitive
+ // dependency on a package that does. These are the only packages
+ // for which we load source code.
+ var stack []*loaderPackage
+ var visit func(lpkg *loaderPackage) bool
+ var srcPkgs []*loaderPackage
+ visit = func(lpkg *loaderPackage) bool {
+ switch lpkg.color {
+ case black:
+ return lpkg.needsrc
+ case grey:
+ panic("internal error: grey node")
+ }
+ lpkg.color = grey
+ stack = append(stack, lpkg) // push
+ stubs := lpkg.Imports // the structure form has only stubs with the ID in the Imports
+ // If NeedImports isn't set, the imports fields will all be zeroed out.
+ if ld.Mode&NeedImports != 0 {
+ lpkg.Imports = make(map[string]*Package, len(stubs))
+ for importPath, ipkg := range stubs {
+ var importErr error
+ imp := ld.pkgs[ipkg.ID]
+ if imp == nil {
+ // (includes package "C" when DisableCgo)
+ importErr = fmt.Errorf("missing package: %q", ipkg.ID)
+ } else if imp.color == grey {
+ importErr = fmt.Errorf("import cycle: %s", stack)
+ }
+ if importErr != nil {
+ if lpkg.importErrors == nil {
+ lpkg.importErrors = make(map[string]error)
+ }
+ lpkg.importErrors[importPath] = importErr
+ continue
+ }
+
+ if visit(imp) {
+ lpkg.needsrc = true
+ }
+ lpkg.Imports[importPath] = imp.Package
+ }
+ }
+ if lpkg.needsrc {
+ srcPkgs = append(srcPkgs, lpkg)
+ }
+ if ld.Mode&NeedTypesSizes != 0 {
+ lpkg.TypesSizes = ld.sizes
+ }
+ stack = stack[:len(stack)-1] // pop
+ lpkg.color = black
+
+ return lpkg.needsrc
+ }
+
+ if ld.Mode&NeedImports == 0 {
+ // We do this to drop the stub import packages that we are not even going to try to resolve.
+ for _, lpkg := range initial {
+ lpkg.Imports = nil
+ }
+ } else {
+ // For each initial package, create its import DAG.
+ for _, lpkg := range initial {
+ visit(lpkg)
+ }
+ }
+ if ld.Mode&NeedImports != 0 && ld.Mode&NeedTypes != 0 {
+ for _, lpkg := range srcPkgs {
+ // Complete type information is required for the
+ // immediate dependencies of each source package.
+ for _, ipkg := range lpkg.Imports {
+ imp := ld.pkgs[ipkg.ID]
+ imp.needtypes = true
+ }
+ }
+ }
+ // Load type data and syntax if needed, starting at
+ // the initial packages (roots of the import DAG).
+ if ld.Mode&NeedTypes != 0 || ld.Mode&NeedSyntax != 0 {
+ var wg sync.WaitGroup
+ for _, lpkg := range initial {
+ wg.Add(1)
+ go func(lpkg *loaderPackage) {
+ ld.loadRecursive(lpkg)
+ wg.Done()
+ }(lpkg)
+ }
+ wg.Wait()
+ }
+
+ result := make([]*Package, len(initial))
+ for i, lpkg := range initial {
+ result[i] = lpkg.Package
+ }
+ for i := range ld.pkgs {
+ // Clear all unrequested fields,
+ // to catch programs that use more than they request.
+ if ld.requestedMode&NeedName == 0 {
+ ld.pkgs[i].Name = ""
+ ld.pkgs[i].PkgPath = ""
+ }
+ if ld.requestedMode&NeedFiles == 0 {
+ ld.pkgs[i].GoFiles = nil
+ ld.pkgs[i].OtherFiles = nil
+ ld.pkgs[i].IgnoredFiles = nil
+ }
+ if ld.requestedMode&NeedCompiledGoFiles == 0 {
+ ld.pkgs[i].CompiledGoFiles = nil
+ }
+ if ld.requestedMode&NeedImports == 0 {
+ ld.pkgs[i].Imports = nil
+ }
+ if ld.requestedMode&NeedExportsFile == 0 {
+ ld.pkgs[i].ExportFile = ""
+ }
+ if ld.requestedMode&NeedTypes == 0 {
+ ld.pkgs[i].Types = nil
+ ld.pkgs[i].Fset = nil
+ ld.pkgs[i].IllTyped = false
+ }
+ if ld.requestedMode&NeedSyntax == 0 {
+ ld.pkgs[i].Syntax = nil
+ }
+ if ld.requestedMode&NeedTypesInfo == 0 {
+ ld.pkgs[i].TypesInfo = nil
+ }
+ if ld.requestedMode&NeedTypesSizes == 0 {
+ ld.pkgs[i].TypesSizes = nil
+ }
+ if ld.requestedMode&NeedModule == 0 {
+ ld.pkgs[i].Module = nil
+ }
+ }
+
+ return result, nil
+}
+
+// loadRecursive loads the specified package and its dependencies,
+// recursively, in parallel, in topological order.
+// It is atomic and idempotent.
+// Precondition: ld.Mode&NeedTypes.
+func (ld *loader) loadRecursive(lpkg *loaderPackage) {
+ lpkg.loadOnce.Do(func() {
+ // Load the direct dependencies, in parallel.
+ var wg sync.WaitGroup
+ for _, ipkg := range lpkg.Imports {
+ imp := ld.pkgs[ipkg.ID]
+ wg.Add(1)
+ go func(imp *loaderPackage) {
+ ld.loadRecursive(imp)
+ wg.Done()
+ }(imp)
+ }
+ wg.Wait()
+ ld.loadPackage(lpkg)
+ })
+}
+
+// loadPackage loads the specified package.
+// It must be called only once per Package,
+// after immediate dependencies are loaded.
+// Precondition: ld.Mode & NeedTypes.
+func (ld *loader) loadPackage(lpkg *loaderPackage) {
+ if lpkg.PkgPath == "unsafe" {
+ // Fill in the blanks to avoid surprises.
+ lpkg.Types = types.Unsafe
+ lpkg.Fset = ld.Fset
+ lpkg.Syntax = []*ast.File{}
+ lpkg.TypesInfo = new(types.Info)
+ lpkg.TypesSizes = ld.sizes
+ return
+ }
+
+ // Call NewPackage directly with explicit name.
+ // This avoids skew between golist and go/types when the files'
+ // package declarations are inconsistent.
+ lpkg.Types = types.NewPackage(lpkg.PkgPath, lpkg.Name)
+ lpkg.Fset = ld.Fset
+
+ // Subtle: we populate all Types fields with an empty Package
+ // before loading export data so that export data processing
+ // never has to create a types.Package for an indirect dependency,
+ // which would then require that such created packages be explicitly
+ // inserted back into the Import graph as a final step after export data loading.
+ // The Diamond test exercises this case.
+ if !lpkg.needtypes && !lpkg.needsrc {
+ return
+ }
+ if !lpkg.needsrc {
+ ld.loadFromExportData(lpkg)
+ return // not a source package, don't get syntax trees
+ }
+
+ appendError := func(err error) {
+ // Convert various error types into the one true Error.
+ var errs []Error
+ switch err := err.(type) {
+ case Error:
+ // from driver
+ errs = append(errs, err)
+
+ case *os.PathError:
+ // from parser
+ errs = append(errs, Error{
+ Pos: err.Path + ":1",
+ Msg: err.Err.Error(),
+ Kind: ParseError,
+ })
+
+ case scanner.ErrorList:
+ // from parser
+ for _, err := range err {
+ errs = append(errs, Error{
+ Pos: err.Pos.String(),
+ Msg: err.Msg,
+ Kind: ParseError,
+ })
+ }
+
+ case types.Error:
+ // from type checker
+ errs = append(errs, Error{
+ Pos: err.Fset.Position(err.Pos).String(),
+ Msg: err.Msg,
+ Kind: TypeError,
+ })
+
+ default:
+ // unexpected impoverished error from parser?
+ errs = append(errs, Error{
+ Pos: "-",
+ Msg: err.Error(),
+ Kind: UnknownError,
+ })
+
+ // If you see this error message, please file a bug.
+ log.Printf("internal error: error %q (%T) without position", err, err)
+ }
+
+ lpkg.Errors = append(lpkg.Errors, errs...)
+ }
+
+ if ld.Config.Mode&NeedTypes != 0 && len(lpkg.CompiledGoFiles) == 0 && lpkg.ExportFile != "" {
+ // The config requested loading sources and types, but sources are missing.
+ // Add an error to the package and fall back to loading from export data.
+ appendError(Error{"-", fmt.Sprintf("sources missing for package %s", lpkg.ID), ParseError})
+ ld.loadFromExportData(lpkg)
+ return // can't get syntax trees for this package
+ }
+
+ files, errs := ld.parseFiles(lpkg.CompiledGoFiles)
+ for _, err := range errs {
+ appendError(err)
+ }
+
+ lpkg.Syntax = files
+ if ld.Config.Mode&NeedTypes == 0 {
+ return
+ }
+
+ lpkg.TypesInfo = &types.Info{
+ Types: make(map[ast.Expr]types.TypeAndValue),
+ Defs: make(map[*ast.Ident]types.Object),
+ Uses: make(map[*ast.Ident]types.Object),
+ Implicits: make(map[ast.Node]types.Object),
+ Scopes: make(map[ast.Node]*types.Scope),
+ Selections: make(map[*ast.SelectorExpr]*types.Selection),
+ }
+ lpkg.TypesSizes = ld.sizes
+
+ importer := importerFunc(func(path string) (*types.Package, error) {
+ if path == "unsafe" {
+ return types.Unsafe, nil
+ }
+
+ // The imports map is keyed by import path.
+ ipkg := lpkg.Imports[path]
+ if ipkg == nil {
+ if err := lpkg.importErrors[path]; err != nil {
+ return nil, err
+ }
+ // There was skew between the metadata and the
+ // import declarations, likely due to an edit
+ // race, or because the ParseFile feature was
+ // used to supply alternative file contents.
+ return nil, fmt.Errorf("no metadata for %s", path)
+ }
+
+ if ipkg.Types != nil && ipkg.Types.Complete() {
+ return ipkg.Types, nil
+ }
+ log.Fatalf("internal error: package %q without types was imported from %q", path, lpkg)
+ panic("unreachable")
+ })
+
+ // type-check
+ tc := &types.Config{
+ Importer: importer,
+
+ // Type-check bodies of functions only in non-initial packages.
+ // Example: for import graph A->B->C and initial packages {A,C},
+ // we can ignore function bodies in B.
+ IgnoreFuncBodies: ld.Mode&NeedDeps == 0 && !lpkg.initial,
+
+ Error: appendError,
+ Sizes: ld.sizes,
+ }
+ if (ld.Mode & typecheckCgo) != 0 {
+ if !typesinternal.SetUsesCgo(tc) {
+ appendError(Error{
+ Msg: "typecheckCgo requires Go 1.15+",
+ Kind: ListError,
+ })
+ return
+ }
+ }
+ types.NewChecker(tc, ld.Fset, lpkg.Types, lpkg.TypesInfo).Files(lpkg.Syntax)
+
+ lpkg.importErrors = nil // no longer needed
+
+ // If !Cgo, the type-checker uses FakeImportC mode, so
+ // it doesn't invoke the importer for import "C",
+ // nor report an error for the import,
+ // or for any undefined C.f reference.
+ // We must detect this explicitly and correctly
+ // mark the package as IllTyped (by reporting an error).
+ // TODO(adonovan): if these errors are annoying,
+ // we could just set IllTyped quietly.
+ if tc.FakeImportC {
+ outer:
+ for _, f := range lpkg.Syntax {
+ for _, imp := range f.Imports {
+ if imp.Path.Value == `"C"` {
+ err := types.Error{Fset: ld.Fset, Pos: imp.Pos(), Msg: `import "C" ignored`}
+ appendError(err)
+ break outer
+ }
+ }
+ }
+ }
+
+ // Record accumulated errors.
+ illTyped := len(lpkg.Errors) > 0
+ if !illTyped {
+ for _, imp := range lpkg.Imports {
+ if imp.IllTyped {
+ illTyped = true
+ break
+ }
+ }
+ }
+ lpkg.IllTyped = illTyped
+}
+
+// An importFunc is an implementation of the single-method
+// types.Importer interface based on a function value.
+type importerFunc func(path string) (*types.Package, error)
+
+func (f importerFunc) Import(path string) (*types.Package, error) { return f(path) }
+
+// We use a counting semaphore to limit
+// the number of parallel I/O calls per process.
+var ioLimit = make(chan bool, 20)
+
+func (ld *loader) parseFile(filename string) (*ast.File, error) {
+ ld.parseCacheMu.Lock()
+ v, ok := ld.parseCache[filename]
+ if ok {
+ // cache hit
+ ld.parseCacheMu.Unlock()
+ <-v.ready
+ } else {
+ // cache miss
+ v = &parseValue{ready: make(chan struct{})}
+ ld.parseCache[filename] = v
+ ld.parseCacheMu.Unlock()
+
+ var src []byte
+ for f, contents := range ld.Config.Overlay {
+ if sameFile(f, filename) {
+ src = contents
+ }
+ }
+ var err error
+ if src == nil {
+ ioLimit <- true // wait
+ src, err = ioutil.ReadFile(filename)
+ <-ioLimit // signal
+ }
+ if err != nil {
+ v.err = err
+ } else {
+ v.f, v.err = ld.ParseFile(ld.Fset, filename, src)
+ }
+
+ close(v.ready)
+ }
+ return v.f, v.err
+}
+
+// parseFiles reads and parses the Go source files and returns the ASTs
+// of the ones that could be at least partially parsed, along with a
+// list of I/O and parse errors encountered.
+//
+// Because files are scanned in parallel, the token.Pos
+// positions of the resulting ast.Files are not ordered.
+//
+func (ld *loader) parseFiles(filenames []string) ([]*ast.File, []error) {
+ var wg sync.WaitGroup
+ n := len(filenames)
+ parsed := make([]*ast.File, n)
+ errors := make([]error, n)
+ for i, file := range filenames {
+ if ld.Config.Context.Err() != nil {
+ parsed[i] = nil
+ errors[i] = ld.Config.Context.Err()
+ continue
+ }
+ wg.Add(1)
+ go func(i int, filename string) {
+ parsed[i], errors[i] = ld.parseFile(filename)
+ wg.Done()
+ }(i, file)
+ }
+ wg.Wait()
+
+ // Eliminate nils, preserving order.
+ var o int
+ for _, f := range parsed {
+ if f != nil {
+ parsed[o] = f
+ o++
+ }
+ }
+ parsed = parsed[:o]
+
+ o = 0
+ for _, err := range errors {
+ if err != nil {
+ errors[o] = err
+ o++
+ }
+ }
+ errors = errors[:o]
+
+ return parsed, errors
+}
+
+// sameFile returns true if x and y have the same basename and denote
+// the same file.
+//
+func sameFile(x, y string) bool {
+ if x == y {
+ // It could be the case that y doesn't exist.
+ // For instance, it may be an overlay file that
+ // hasn't been written to disk. To handle that case
+ // let x == y through. (We added the exact absolute path
+ // string to the CompiledGoFiles list, so the unwritten
+ // overlay case implies x==y.)
+ return true
+ }
+ if strings.EqualFold(filepath.Base(x), filepath.Base(y)) { // (optimisation)
+ if xi, err := os.Stat(x); err == nil {
+ if yi, err := os.Stat(y); err == nil {
+ return os.SameFile(xi, yi)
+ }
+ }
+ }
+ return false
+}
+
+// loadFromExportData returns type information for the specified
+// package, loading it from an export data file on the first request.
+func (ld *loader) loadFromExportData(lpkg *loaderPackage) (*types.Package, error) {
+ if lpkg.PkgPath == "" {
+ log.Fatalf("internal error: Package %s has no PkgPath", lpkg)
+ }
+
+ // Because gcexportdata.Read has the potential to create or
+ // modify the types.Package for each node in the transitive
+ // closure of dependencies of lpkg, all exportdata operations
+ // must be sequential. (Finer-grained locking would require
+ // changes to the gcexportdata API.)
+ //
+ // The exportMu lock guards the Package.Pkg field and the
+ // types.Package it points to, for each Package in the graph.
+ //
+ // Not all accesses to Package.Pkg need to be protected by exportMu:
+ // graph ordering ensures that direct dependencies of source
+ // packages are fully loaded before the importer reads their Pkg field.
+ ld.exportMu.Lock()
+ defer ld.exportMu.Unlock()
+
+ if tpkg := lpkg.Types; tpkg != nil && tpkg.Complete() {
+ return tpkg, nil // cache hit
+ }
+
+ lpkg.IllTyped = true // fail safe
+
+ if lpkg.ExportFile == "" {
+ // Errors while building export data will have been printed to stderr.
+ return nil, fmt.Errorf("no export data file")
+ }
+ f, err := os.Open(lpkg.ExportFile)
+ if err != nil {
+ return nil, err
+ }
+ defer f.Close()
+
+ // Read gc export data.
+ //
+ // We don't currently support gccgo export data because all
+ // underlying workspaces use the gc toolchain. (Even build
+ // systems that support gccgo don't use it for workspace
+ // queries.)
+ r, err := gcexportdata.NewReader(f)
+ if err != nil {
+ return nil, fmt.Errorf("reading %s: %v", lpkg.ExportFile, err)
+ }
+
+ // Build the view.
+ //
+ // The gcexportdata machinery has no concept of package ID.
+ // It identifies packages by their PkgPath, which although not
+ // globally unique is unique within the scope of one invocation
+ // of the linker, type-checker, or gcexportdata.
+ //
+ // So, we must build a PkgPath-keyed view of the global
+ // (conceptually ID-keyed) cache of packages and pass it to
+ // gcexportdata. The view must contain every existing
+ // package that might possibly be mentioned by the
+ // current package---its transitive closure.
+ //
+ // In loadPackage, we unconditionally create a types.Package for
+ // each dependency so that export data loading does not
+ // create new ones.
+ //
+ // TODO(adonovan): it would be simpler and more efficient
+ // if the export data machinery invoked a callback to
+ // get-or-create a package instead of a map.
+ //
+ view := make(map[string]*types.Package) // view seen by gcexportdata
+ seen := make(map[*loaderPackage]bool) // all visited packages
+ var visit func(pkgs map[string]*Package)
+ visit = func(pkgs map[string]*Package) {
+ for _, p := range pkgs {
+ lpkg := ld.pkgs[p.ID]
+ if !seen[lpkg] {
+ seen[lpkg] = true
+ view[lpkg.PkgPath] = lpkg.Types
+ visit(lpkg.Imports)
+ }
+ }
+ }
+ visit(lpkg.Imports)
+
+ viewLen := len(view) + 1 // adding the self package
+ // Parse the export data.
+ // (May modify incomplete packages in view but not create new ones.)
+ tpkg, err := gcexportdata.Read(r, ld.Fset, view, lpkg.PkgPath)
+ if err != nil {
+ return nil, fmt.Errorf("reading %s: %v", lpkg.ExportFile, err)
+ }
+ if viewLen != len(view) {
+ log.Fatalf("Unexpected package creation during export data loading")
+ }
+
+ lpkg.Types = tpkg
+ lpkg.IllTyped = false
+
+ return tpkg, nil
+}
+
+// impliedLoadMode returns loadMode with its dependencies.
+func impliedLoadMode(loadMode LoadMode) LoadMode {
+ if loadMode&NeedTypesInfo != 0 && loadMode&NeedImports == 0 {
+ // If NeedTypesInfo, go/packages needs to do typechecking itself so it can
+ // associate type info with the AST. To do so, we need the export data
+ // for dependencies, which means we need to ask for the direct dependencies.
+ // NeedImports is used to ask for the direct dependencies.
+ loadMode |= NeedImports
+ }
+
+ if loadMode&NeedDeps != 0 && loadMode&NeedImports == 0 {
+ // With NeedDeps we need to load at least direct dependencies.
+ // NeedImports is used to ask for the direct dependencies.
+ loadMode |= NeedImports
+ }
+
+ return loadMode
+}
+
+func usesExportData(cfg *Config) bool {
+ return cfg.Mode&NeedExportsFile != 0 || cfg.Mode&NeedTypes != 0 && cfg.Mode&NeedDeps == 0
+}
projects / dotfiles / .git / blobdiff