| // Copyright 2019 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 cache |
| |
| import ( |
| "context" |
| "io" |
| "io/ioutil" |
| "os" |
| "strings" |
| |
| "golang.org/x/tools/internal/lsp/source" |
| "golang.org/x/tools/internal/lsp/telemetry" |
| "golang.org/x/tools/internal/telemetry/log" |
| errors "golang.org/x/xerrors" |
| ) |
| |
| // This function will return the main go.mod file for this folder if it exists and whether the -modfile |
| // flag exists for this version of go. |
| func modfileFlagExists(ctx context.Context, folder string, env []string) (string, bool, error) { |
| // Check the Go version by running go list with GO111MODULE=off. |
| // If the output is anything other than "go1.14\n", assume -modfile is not supported. |
| // Borrowed from internal/imports/mod.go:620 |
| const format = `{{range context.ReleaseTags}}{{if eq . "go1.14"}}{{.}}{{end}}{{end}}` |
| stdout, err := source.InvokeGo(ctx, folder, append(env, "GO111MODULE=off"), "list", "-e", "-f", format) |
| if err != nil { |
| return "", false, err |
| } |
| // If the output is not go1.14 or an empty string, then it could be an error. |
| lines := strings.Split(stdout.String(), "\n") |
| if len(lines) < 2 && stdout.String() != "" { |
| log.Error(ctx, "unexpected stdout when checking for go1.14", errors.Errorf("%q", stdout), telemetry.Directory.Of(folder)) |
| return "", false, nil |
| } |
| // Get the go.mod file associated with this module. |
| b, err := source.InvokeGo(ctx, folder, env, "env", "GOMOD") |
| if err != nil { |
| return "", false, err |
| } |
| modfile := strings.TrimSpace(b.String()) |
| if modfile == os.DevNull { |
| return "", false, errors.Errorf("go env GOMOD did not detect a go.mod file in this folder") |
| } |
| return modfile, lines[0] == "go1.14", nil |
| } |
| |
| // The function getModfiles will return the go.mod files associated with the directory that is passed in. |
| func getModfiles(ctx context.Context, folder string, options source.Options) (*modfiles, error) { |
| if !options.TempModfile { |
| log.Print(ctx, "using the -modfile flag is disabled", telemetry.Directory.Of(folder)) |
| return nil, nil |
| } |
| modfile, flagExists, err := modfileFlagExists(ctx, folder, options.Env) |
| if err != nil { |
| return nil, err |
| } |
| if !flagExists { |
| return nil, nil |
| } |
| if modfile == "" || modfile == os.DevNull { |
| return nil, errors.Errorf("go env GOMOD cannot detect a go.mod file in this folder") |
| } |
| // Copy the current go.mod file into the temporary go.mod file. |
| tempFile, err := ioutil.TempFile("", "go.*.mod") |
| if err != nil { |
| return nil, err |
| } |
| defer tempFile.Close() |
| origFile, err := os.Open(modfile) |
| if err != nil { |
| return nil, err |
| } |
| defer origFile.Close() |
| if _, err := io.Copy(tempFile, origFile); err != nil { |
| return nil, err |
| } |
| copySumFile(modfile, tempFile.Name()) |
| return &modfiles{real: modfile, temp: tempFile.Name()}, nil |
| } |
| |
| func copySumFile(realFile, tempFile string) { |
| realSum := realFile[0:len(realFile)-3] + "sum" |
| tempSum := tempFile[0:len(tempFile)-3] + "sum" |
| stat, err := os.Stat(realSum) |
| if err != nil || !stat.Mode().IsRegular() { |
| return |
| } |
| contents, err := ioutil.ReadFile(realSum) |
| if err != nil { |
| return |
| } |
| ioutil.WriteFile(tempSum, contents, stat.Mode()) |
| } |