Merge pull request #409 from xushiwei/q

gogen/packages: optional DiskCache
goplus · Mar 24, 2024 · 37ef51d · 37ef51d
2 parents d435e48 + 0986cf9
commit 37ef51d
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Showing 2 changed files with 45 additions and 5 deletions.
diff --git a/packages/imp.go b/packages/imp.go
@@ -27,14 +27,19 @@ import (
 
 // ----------------------------------------------------------------------------
 
+type DiskCache interface {
+	Find(dir, pkgPath string) (expfile string, err error)
+}
+
 type Importer struct {
 	loaded map[string]*types.Package
 	fset   *token.FileSet
 	dir    string
+	cache  DiskCache
 	m      sync.RWMutex
 }
 
-// NewImporter creates an Importer object that meets types.Importer interface.
+// NewImporter creates an Importer object that meets types.ImporterFrom and types.Importer interface.
 func NewImporter(fset *token.FileSet, workDir ...string) *Importer {
 	dir := ""
 	if len(workDir) > 0 {
@@ -48,6 +53,11 @@ func NewImporter(fset *token.FileSet, workDir ...string) *Importer {
 	return &Importer{loaded: loaded, fset: fset, dir: dir}
 }
 
+// SetDiskCache sets an optional disk cache for the importer.
+func (p *Importer) SetDiskCache(cache DiskCache) {
+	p.cache = cache
+}
+
 func (p *Importer) Import(pkgPath string) (pkg *types.Package, err error) {
 	return p.ImportFrom(pkgPath, p.dir, 0)
 }
@@ -68,7 +78,7 @@ func (p *Importer) ImportFrom(pkgPath, dir string, mode types.ImportMode) (*type
 		return ret, nil
 	}
 	p.m.RUnlock()
-	expfile, err := FindExport(dir, pkgPath)
+	expfile, err := p.findExport(dir, pkgPath)
 	if err != nil {
 		return nil, err
 	}
@@ -93,9 +103,12 @@ func (p *Importer) loadByExport(expfile string, pkgPath string) (ret *types.Pack
 
 // ----------------------------------------------------------------------------
 
-// FindExport lookups export file (.a) of a package by its pkgPath.
+// findExport lookups export file (.a) of a package by its pkgPath.
 // It returns empty if pkgPath not found.
-func FindExport(dir, pkgPath string) (expfile string, err error) {
+func (p *Importer) findExport(dir, pkgPath string) (expfile string, err error) {
+	if c := p.cache; c != nil {
+		return c.Find(dir, pkgPath)
+	}
 	data, err := golistExport(dir, pkgPath)
 	if err != nil {
 		return

diff --git a/packages/imp_test.go b/packages/imp_test.go
@@ -53,7 +53,34 @@ func Test_loadByExport(t *testing.T) {
 	if _, err := p.loadByExport("/not-found", "notfound"); !os.IsNotExist(err) {
 		t.Fatal("Test_loadByExport: no error?")
 	}
-	FindExport(".", "C")
+	p.findExport(".", "C")
+}
+
+// ----------------------------------------------------------------------------
+
+type diskCache struct {
+	imp *Importer
+}
+
+func (p diskCache) Find(dir, pkgPath string) (expfile string, err error) {
+	if p.imp != nil {
+		return p.imp.findExport(dir, pkgPath)
+	}
+	return "", os.ErrNotExist
+}
+
+func TestDiskCache(t *testing.T) {
+	p := NewImporter(nil)
+	p.SetDiskCache(diskCache{})
+	_, err := p.Import("fmt")
+	if err != os.ErrNotExist {
+		t.Fatal("Import:", err)
+	}
+	p.SetDiskCache(diskCache{imp: NewImporter(nil)})
+	pkg, err := p.Import("fmt")
+	if err != nil || pkg.Path() != "fmt" {
+		t.Fatal("Import fmt:", pkg, err)
+	}
 }
 
 // ----------------------------------------------------------------------------