| // Copyright 2017 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 base |
| |
| import ( |
| "fmt" |
| "go/build" |
| "os" |
| "path/filepath" |
| |
| "cmd/go/internal/cfg" |
| "cmd/go/internal/par" |
| ) |
| |
| // Tool returns the path to the named tool (for example, "vet"). |
| // If the tool cannot be found, Tool exits the process. |
| func Tool(toolName string) string { |
| toolPath, err := ToolPath(toolName) |
| if err != nil && len(cfg.BuildToolexec) == 0 { |
| // Give a nice message if there is no tool with that name. |
| fmt.Fprintf(os.Stderr, "go: no such tool %q\n", toolName) |
| SetExitStatus(2) |
| Exit() |
| } |
| return toolPath |
| } |
| |
| // ToolPath returns the path at which we expect to find the named tool |
| // (for example, "vet"), and the error (if any) from statting that path. |
| func ToolPath(toolName string) (string, error) { |
| toolPath := filepath.Join(build.ToolDir, toolName) + cfg.ToolExeSuffix() |
| err := toolStatCache.Do(toolPath, func() error { |
| _, err := os.Stat(toolPath) |
| return err |
| }) |
| return toolPath, err |
| } |
| |
| var toolStatCache par.Cache[string, error] |