From 74a9317c83685100ee5496f6aa552366a0f63eee Mon Sep 17 00:00:00 2001
From: Carlos Alexandro Becker <caarlos0@users.noreply.github.com>
Date: Sat, 4 Nov 2023 01:59:25 +0000
Subject: [PATCH] fix: properly handle multi-module projects with a go.work
 file

closes #4379
---
 internal/pipe/gomod/gomod.go                |  5 ++-
 internal/pipe/gomod/gomod_test.go           | 39 +++++++++++++++++++++
 www/docs/customization/verifiable_builds.md |  7 ++++
 3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/internal/pipe/gomod/gomod.go b/internal/pipe/gomod/gomod.go
index 8d474652211..4fb99bfb901 100644
--- a/internal/pipe/gomod/gomod.go
+++ b/internal/pipe/gomod/gomod.go
@@ -48,6 +48,9 @@ func (Pipe) Run(ctx *context.Context) error {
 		return fmt.Errorf("failed to get module path: %w: %s", err, string(out))
 	}
 
-	ctx.ModulePath = result
+	// Splits and use the first line in case a `go.work` file exists with multiple modules.
+	// The first module is/should be `.` in the `go.work` file, so this should be correct.
+	// Running `go work sync` also always puts `.` as the first line in `use`.
+	ctx.ModulePath = strings.Split(result, "\n")[0]
 	return nil
 }
diff --git a/internal/pipe/gomod/gomod_test.go b/internal/pipe/gomod/gomod_test.go
index f6c59d2ea03..61e2f87af0a 100644
--- a/internal/pipe/gomod/gomod_test.go
+++ b/internal/pipe/gomod/gomod_test.go
@@ -2,7 +2,9 @@ package gomod
 
 import (
 	"os"
+	"os/exec"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/goreleaser/goreleaser/internal/testctx"
@@ -18,6 +20,43 @@ func TestRun(t *testing.T) {
 	require.Equal(t, "github.com/goreleaser/goreleaser", ctx.ModulePath)
 }
 
+func TestRunGoWork(t *testing.T) {
+	dir := testlib.Mktmp(t)
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "main.go"),
+		[]byte("package main\nfunc main() {println(0)}"),
+		0o666,
+	))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "go.mod"),
+		[]byte("module a"),
+		0o666,
+	))
+	require.NoError(t, os.Mkdir(filepath.Join(dir, "b"), 0o755))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "b", "main.go"),
+		[]byte("package main\nfunc main() {println(1)}"),
+		0o666,
+	))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "b", "go.mod"),
+		[]byte("module a/b"),
+		0o666,
+	))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "go.work"),
+		[]byte("use (\n\t.\n\tb\n)"),
+		0o666,
+	))
+	out, err := exec.Command("go", "list", "-m").CombinedOutput()
+	require.NoError(t, err)
+	require.Equal(t, "a\na/b", strings.TrimSpace(string(out)))
+	ctx := testctx.New()
+	require.NoError(t, Pipe{}.Default(ctx))
+	require.NoError(t, Pipe{}.Run(ctx))
+	require.Equal(t, "a", ctx.ModulePath)
+}
+
 func TestRunCustomMod(t *testing.T) {
 	ctx := testctx.NewWithCfg(config.Project{
 		GoMod: config.GoMod{
diff --git a/www/docs/customization/verifiable_builds.md b/www/docs/customization/verifiable_builds.md
index fea3753d022..a2e7c9fc928 100644
--- a/www/docs/customization/verifiable_builds.md
+++ b/www/docs/customization/verifiable_builds.md
@@ -40,11 +40,18 @@ gomod:
 ```
 
 !!! tip
+
     You can use `debug.ReadBuildInfo()` to get the version/checksum/dependencies
     of the module.
 
 !!! warning
+
     VCS Info will not be embedded in the binary, as in practice it is not being
     built from the source, but from the Go Mod Proxy.
 
+!!! warning 
+
+    If you have a `go.work` file, make sure to run `go work sync`, so the main
+    module (`.`) is the first line inside the `use` block.
+
 [vgo]: https://research.swtch.com/vgo-repro