From d6511e5e9f58a975b5568d11282c30bc70bdc2e5 Mon Sep 17 00:00:00 2001 From: Alan Donovan Date: Fri, 21 Oct 2022 13:13:46 -0400 Subject: [PATCH] internal/facts: share go/analysis/internal/facts with gopls This change moves the facts package so that it can be reused by gopls. It remains a tools-internal API. A forthcoming reimplementation of gopls's analysis driver will make use of the new packages and the features mentioned below. Also: - change parameter of read() callback from 'path string' to *Package. - use NewDecoder().Decode() to amortize import-map computation across calls. Change-Id: Id10cd02c0c241353524d568d5299d81457f571f8 Reviewed-on: https://go-review.googlesource.com/c/tools/+/444796 Reviewed-by: Tim King Reviewed-by: Robert Findley Run-TryBot: Alan Donovan --- go/analysis/unitchecker/unitchecker.go | 8 ++--- .../internal => internal}/facts/facts.go | 35 +++++++++++++------ .../internal => internal}/facts/facts_test.go | 10 +++--- .../internal => internal}/facts/imports.go | 3 ++ 4 files changed, 36 insertions(+), 20 deletions(-) rename {go/analysis/internal => internal}/facts/facts.go (91%) rename {go/analysis/internal => internal}/facts/facts_test.go (96%) rename {go/analysis/internal => internal}/facts/imports.go (95%) diff --git a/go/analysis/unitchecker/unitchecker.go b/go/analysis/unitchecker/unitchecker.go index 9827b57f52..d9c8f11cdd 100644 --- a/go/analysis/unitchecker/unitchecker.go +++ b/go/analysis/unitchecker/unitchecker.go @@ -50,7 +50,7 @@ import ( "golang.org/x/tools/go/analysis" "golang.org/x/tools/go/analysis/internal/analysisflags" - "golang.org/x/tools/go/analysis/internal/facts" + "golang.org/x/tools/internal/facts" "golang.org/x/tools/internal/typeparams" ) @@ -287,13 +287,13 @@ func run(fset *token.FileSet, cfg *Config, analyzers []*analysis.Analyzer) ([]re analyzers = filtered // Read facts from imported packages. - read := func(path string) ([]byte, error) { - if vetx, ok := cfg.PackageVetx[path]; ok { + read := func(imp *types.Package) ([]byte, error) { + if vetx, ok := cfg.PackageVetx[imp.Path()]; ok { return ioutil.ReadFile(vetx) } return nil, nil // no .vetx file, no facts } - facts, err := facts.Decode(pkg, read) + facts, err := facts.NewDecoder(pkg).Decode(read) if err != nil { return nil, err } diff --git a/go/analysis/internal/facts/facts.go b/internal/facts/facts.go similarity index 91% rename from go/analysis/internal/facts/facts.go rename to internal/facts/facts.go index 006abab84e..81df45161a 100644 --- a/go/analysis/internal/facts/facts.go +++ b/internal/facts/facts.go @@ -152,6 +152,23 @@ type gobFact struct { Fact analysis.Fact // type and value of user-defined Fact } +// A Decoder decodes the facts from the direct imports of the package +// provided to NewEncoder. A single decoder may be used to decode +// multiple fact sets (e.g. each for a different set of fact types) +// for the same package. Each call to Decode returns an independent +// fact set. +type Decoder struct { + pkg *types.Package + packages map[string]*types.Package +} + +// NewDecoder returns a fact decoder for the specified package. +func NewDecoder(pkg *types.Package) *Decoder { + // Compute the import map for this package. + // See the package doc comment. + return &Decoder{pkg, importMap(pkg.Imports())} +} + // Decode decodes all the facts relevant to the analysis of package pkg. // The read function reads serialized fact data from an external source // for one of of pkg's direct imports. The empty file is a valid @@ -159,28 +176,24 @@ type gobFact struct { // // It is the caller's responsibility to call gob.Register on all // necessary fact types. -func Decode(pkg *types.Package, read func(packagePath string) ([]byte, error)) (*Set, error) { - // Compute the import map for this package. - // See the package doc comment. - packages := importMap(pkg.Imports()) - +func (d *Decoder) Decode(read func(*types.Package) ([]byte, error)) (*Set, error) { // Read facts from imported packages. // Facts may describe indirectly imported packages, or their objects. m := make(map[key]analysis.Fact) // one big bucket - for _, imp := range pkg.Imports() { + for _, imp := range d.pkg.Imports() { logf := func(format string, args ...interface{}) { if debug { prefix := fmt.Sprintf("in %s, importing %s: ", - pkg.Path(), imp.Path()) + d.pkg.Path(), imp.Path()) log.Print(prefix, fmt.Sprintf(format, args...)) } } // Read the gob-encoded facts. - data, err := read(imp.Path()) + data, err := read(imp) if err != nil { return nil, fmt.Errorf("in %s, can't import facts for package %q: %v", - pkg.Path(), imp.Path(), err) + d.pkg.Path(), imp.Path(), err) } if len(data) == 0 { continue // no facts @@ -195,7 +208,7 @@ func Decode(pkg *types.Package, read func(packagePath string) ([]byte, error)) ( // Parse each one into a key and a Fact. for _, f := range gobFacts { - factPkg := packages[f.PkgPath] + factPkg := d.packages[f.PkgPath] if factPkg == nil { // Fact relates to a dependency that was // unused in this translation unit. Skip. @@ -222,7 +235,7 @@ func Decode(pkg *types.Package, read func(packagePath string) ([]byte, error)) ( } } - return &Set{pkg: pkg, m: m}, nil + return &Set{pkg: d.pkg, m: m}, nil } // Encode encodes a set of facts to a memory buffer. diff --git a/go/analysis/internal/facts/facts_test.go b/internal/facts/facts_test.go similarity index 96% rename from go/analysis/internal/facts/facts_test.go rename to internal/facts/facts_test.go index c8379c58aa..5c7b12ef1d 100644 --- a/go/analysis/internal/facts/facts_test.go +++ b/internal/facts/facts_test.go @@ -14,8 +14,8 @@ import ( "testing" "golang.org/x/tools/go/analysis/analysistest" - "golang.org/x/tools/go/analysis/internal/facts" "golang.org/x/tools/go/packages" + "golang.org/x/tools/internal/facts" "golang.org/x/tools/internal/testenv" "golang.org/x/tools/internal/typeparams" ) @@ -216,7 +216,7 @@ type pkgLookups struct { // are passed during analysis. It operates on a group of Go file contents. Then // for each in tests it does the following: // 1. loads and type checks the package, -// 2. calls facts.Decode to loads the facts exported by its imports, +// 2. calls (*facts.Decoder).Decode to load the facts exported by its imports, // 3. exports a myFact Fact for all of package level objects, // 4. For each lookup for the current package: // 4.a) lookup the types.Object for an Go source expression in the curent package @@ -239,7 +239,7 @@ func testEncodeDecode(t *testing.T, files map[string]string, tests []pkgLookups) // factmap represents the passing of encoded facts from one // package to another. In practice one would use the file system. factmap := make(map[string][]byte) - read := func(path string) ([]byte, error) { return factmap[path], nil } + read := func(imp *types.Package) ([]byte, error) { return factmap[imp.Path()], nil } // Analyze packages in order, look up various objects accessible within // each package, and see if they have a fact. The "analysis" exports a @@ -255,7 +255,7 @@ func testEncodeDecode(t *testing.T, files map[string]string, tests []pkgLookups) } // decode - facts, err := facts.Decode(pkg, read) + facts, err := facts.NewDecoder(pkg).Decode(read) if err != nil { t.Fatalf("Decode failed: %v", err) } @@ -357,7 +357,7 @@ func TestFactFilter(t *testing.T) { } obj := pkg.Scope().Lookup("A") - s, err := facts.Decode(pkg, func(string) ([]byte, error) { return nil, nil }) + s, err := facts.NewDecoder(pkg).Decode(func(*types.Package) ([]byte, error) { return nil, nil }) if err != nil { t.Fatal(err) } diff --git a/go/analysis/internal/facts/imports.go b/internal/facts/imports.go similarity index 95% rename from go/analysis/internal/facts/imports.go rename to internal/facts/imports.go index 8a5553e2e9..a3aa90dd1c 100644 --- a/go/analysis/internal/facts/imports.go +++ b/internal/facts/imports.go @@ -20,6 +20,9 @@ import ( // // Packages in the map that are only indirectly imported may be // incomplete (!pkg.Complete()). +// +// TODO(adonovan): opt: compute this information more efficiently +// by obtaining it from the internals of the gcexportdata decoder. func importMap(imports []*types.Package) map[string]*types.Package { objects := make(map[types.Object]bool) packages := make(map[string]*types.Package)