Ejemplo n.º 1
0
func actionImport(s *Session, arg string) error {
	if arg == "" {
		return fmt.Errorf("arg required")
	}

	path := strings.Trim(arg, `"`)

	// check if the package specified by path is importable
	_, err := types.DefaultImport(s.Types.Packages, path)
	if err != nil {
		return err
	}

	astutil.AddImport(s.Fset, s.File, path)

	return nil
}
Ejemplo n.º 2
0
func fixImports(fset *token.FileSet, f *ast.File) (added []string, err error) {
	// refs are a set of possible package references currently unsatisfied by imports.
	// first key: either base package (e.g. "fmt") or renamed package
	// second key: referenced package symbol (e.g. "Println")
	refs := make(map[string]map[string]bool)

	// decls are the current package imports. key is base package or renamed package.
	decls := make(map[string]*ast.ImportSpec)

	// collect potential uses of packages.
	var visitor visitFn
	visitor = visitFn(func(node ast.Node) ast.Visitor {
		if node == nil {
			return visitor
		}
		switch v := node.(type) {
		case *ast.ImportSpec:
			if v.Name != nil {
				decls[v.Name.Name] = v
			} else {
				local := importPathToName(strings.Trim(v.Path.Value, `\"`))
				decls[local] = v
			}
		case *ast.SelectorExpr:
			xident, ok := v.X.(*ast.Ident)
			if !ok {
				break
			}
			if xident.Obj != nil {
				// if the parser can resolve it, it's not a package ref
				break
			}
			pkgName := xident.Name
			if refs[pkgName] == nil {
				refs[pkgName] = make(map[string]bool)
			}
			if decls[pkgName] == nil {
				refs[pkgName][v.Sel.Name] = true
			}
		}
		return visitor
	})
	ast.Walk(visitor, f)

	// Nil out any unused ImportSpecs, to be removed in following passes
	unusedImport := map[string]bool{}
	for pkg, is := range decls {
		if refs[pkg] == nil && pkg != "_" && pkg != "." {
			unusedImport[strings.Trim(is.Path.Value, `"`)] = true
		}
	}
	for ipath := range unusedImport {
		if ipath == "C" {
			// Don't remove cgo stuff.
			continue
		}
		astutil.DeleteImport(fset, f, ipath)
	}

	// Search for imports matching potential package references.
	searches := 0
	type result struct {
		ipath string
		name  string
		err   error
	}
	results := make(chan result)
	for pkgName, symbols := range refs {
		if len(symbols) == 0 {
			continue // skip over packages already imported
		}
		go func(pkgName string, symbols map[string]bool) {
			ipath, rename, err := findImport(pkgName, symbols)
			r := result{ipath: ipath, err: err}
			if rename {
				r.name = pkgName
			}
			results <- r
		}(pkgName, symbols)
		searches++
	}
	for i := 0; i < searches; i++ {
		result := <-results
		if result.err != nil {
			return nil, result.err
		}
		if result.ipath != "" {
			if result.name != "" {
				astutil.AddNamedImport(fset, f, result.name, result.ipath)
			} else {
				astutil.AddImport(fset, f, result.ipath)
			}
			added = append(added, result.ipath)
		}
	}

	return added, nil
}