x/tools/gopls: gopls imports -w <file> does not update the imports statement

[nickwells]

ATTENTION: Please answer these questions BEFORE submitting your issue. Thanks!

What did you do?

When I run "gopls" from within a Go program (using the exec package) against a file in a temporary directory in macOS the imports statement is not updated if I give the full pathname but is if I give a relative pathname.

Note:

• this only happens on a Mac, not on Linux
• It only happens if I run gopls from within a Go program, running it from the command line works
• it only happens if I run it for a file within a newly created temp dir as generated by calling os.MkdirTemp("", ...), a temp dir in my home directory doesn't have this problem (but one in "/tmp" has the same problem)
• only the imports subcommand has a problem, "gopls format -w " successfully updates the file
• other import statement generators work - "goimports -w " successfully updates the file

The following program demonstrates the issue:

package main

import (
	"flag"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
)

const (
	filename      = "ggg.go"
	progname      = "ggg"
	tmpDirPattern = "ggg-*"

	fileTextStr = `package main
func main() {
fmt.Println("Hello")
}

`
)

var fileText = []byte(fileTextStr)

// execCmd ...
func execCmd(prog string, args ...string) {
	name := prog + " " + strings.Join(args, " ")
	fmt.Println(name)

	cmd := exec.Command(prog, args...)
	cmd.Stdout, cmd.Stderr = os.Stdout, os.Stderr
	err := cmd.Run()

	reportErr(name, err)
}

// reportErr reports the error if not nil and exits
func reportErr(name string, err error) {
	if err == nil {
		return
	}
	fmt.Println(name+": Error: ", err)
	os.Exit(1)
}

// cmp compares the contents of the file with the supplied original text. If
// they differ it will report the difference
func cmp(origText []byte, fileName string, showFileDiffs bool) {
	text, err := os.ReadFile(fileName)
	reportErr("reading file: "+fileName, err)
	differs := len(origText) != len(text)

	if !differs {
		for i, ch := range origText {
			if text[i] != ch {
				differs = true
				break
			}
		}
	}

	if !differs {
		fmt.Println("File is unchanged")
	} else {
		fmt.Println("File has changed")
		if showFileDiffs {
			fmt.Println("Before")
			fmt.Println(string(origText))
			fmt.Println("After")
			fmt.Println(string(text))
		}
	}
}

func main() {
	var desc,
		tmpDir string
	var goplsAct = "imports"

	var useRelName,
		useGoImports,
		showFileDiffs bool

	flag.BoolVar(&useRelName, "rel", false, "use the relative pathname")
	flag.BoolVar(&showFileDiffs, "show", false, "show the differences")
	flag.BoolVar(&useGoImports, "use-goimp", false, "use goimports not gopls")
	flag.StringVar(&tmpDir, "tmp", "", "use this as base temp dir")
	flag.StringVar(&goplsAct, "act", "imports", "the gopls action")
	flag.Parse()

	desc = `MkdirTemp("` + tmpDir + `", "` + tmpDirPattern + `")`
	fmt.Println(desc)
	dir, err := os.MkdirTemp(tmpDir, tmpDirPattern)
	reportErr(desc, err)

	desc = "Chdir " + dir
	fmt.Println(desc)
	err = os.Chdir(dir)
	reportErr(desc, err)

	execCmd("go", "mod", "init", progname)

	desc = "WriteFile " + filename
	fmt.Println(desc)
	err = os.WriteFile(filename, fileText, 0666)
	reportErr(desc, err)

	filePath := filepath.Join(dir, filename)
	if useRelName {
		filePath = filename
	}
	if useGoImports {
		execCmd("goimports", "-w", filePath)
	} else {
		execCmd("gopls", goplsAct, "-w", filePath)
	}
	cmp(fileText, filePath, showFileDiffs)

	execCmd("go", "mod", "tidy")

	execCmd("go", "build")

	execPath := filepath.Join(dir, progname)
	execCmd(execPath)
}

What did you expect to see?

I expected the Go program to have the imports statement filled in

What did you see instead?

The file was unchanged

Build info

the OS version as given by uname -a is

Darwin Nicholass-MBP.broadband 21.6.0 Darwin Kernel Version 21.6.0: Mon Dec 19 20:44:01 PST 2022; root:xnu-8020.240.18~2/RELEASE_X86_64 x86_64

golang.org/x/tools/gopls v0.11.0
    golang.org/x/tools/gopls@v0.11.0 h1:/nvKHdTtePQmrv9XN3gIUN9MOdUrKzO/dcqgbG6x8EY=
    github.com/BurntSushi/toml@v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
    github.com/google/go-cmp@v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
    github.com/sergi/go-diff@v1.1.0 h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0=
    golang.org/x/exp@v0.0.0-20221031165847-c99f073a8326 h1:QfTh0HpN6hlw6D3vu8DAwC8pBIwikq0AI1evdm+FksE=
    golang.org/x/exp/typeparams@v0.0.0-20221031165847-c99f073a8326 h1:fl8k2zg28yA23264d82M4dp+YlJ3ngDcpuB1bewkQi4=
    golang.org/x/mod@v0.7.0 h1:LapD9S96VoQRhi/GrNTqeBJFrUjs5UHCAtTlgwA5oZA=
    golang.org/x/sync@v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
    golang.org/x/sys@v0.2.0 h1:ljd4t30dBnAvMZaQCevtY0xLLD0A+bRZXbgLMLU1F/A=
    golang.org/x/text@v0.4.0 h1:BrVqGRd7+k1DiOgtnFvAkoQEWQvBc25ouMJM6429SFg=
    golang.org/x/tools@v0.3.1-0.20221213193459-ca17b2c27ca8 h1:7/HkGkN/2ktghBCSRRgp31wAww4syfsW52tj7yirjWk=
    golang.org/x/vuln@v0.0.0-20221109205719-3af8368ee4fe h1:qptQiQwEpETwDiz85LKtChqif9xhVkAm8Nhxs0xnTww=
    honnef.co/go/tools@v0.3.3 h1:oDx7VAwstgpYpb3wv0oxiZlxY+foCpRAwY7Vk6XpAgA=
    mvdan.cc/gofumpt@v0.4.0 h1:JVf4NN1mIpHogBj7ABpgOyZc65/UUOkKQFkoURsz4MM=
    mvdan.cc/xurls/v2@v2.4.0 h1:tzxjVAj+wSBmDcF6zBB7/myTy3gX9xvi8Tyr28AuQgc=
go: go1.20.1