fix: handle build.main being a go file when using gomod.proxy (#2173)

* fix: handle build.main being a go file when using gomod.proxy

Signed-off-by: Carlos Alexandro Becker <caarlos0@gmail.com>

* fix: guess pkg

Signed-off-by: Carlos Alexandro Becker <caarlos0@gmail.com>

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

internal/pipe/gomod/gomod.go

@@ -120,6 +120,11 @@ func (e ErrProxy) Unwrap() error {
 
 func proxyBuild(ctx *context.Context, build *config.Build) error {
 	mainPackage := path.Join(ctx.ModulePath, build.Main)
+	if strings.HasSuffix(build.Main, ".go") {
+		pkg := path.Dir(build.Main)
+		log.Warnf("guessing package of '%s' to be '%s', if this is incorrect, setup 'build.%s.main' to be the correct package", build.Main, pkg, build.ID)
+		mainPackage = path.Join(ctx.ModulePath, pkg)
+	}
 	template := tmpl.New(ctx).WithExtraFields(tmpl.Fields{
 		"Main":    mainPackage,
 		"BuildID": build.ID,

internal/pipe/gomod/gomod_test.go

@@ -184,6 +184,37 @@ func TestGoModProxy(t *testing.T) {
 			})
 		}
 	})
+
+	t.Run("goreleaser with main.go", func(t *testing.T) {
+		dir := testlib.Mktmp(t)
+		dist := filepath.Join(dir, "dist")
+		ctx := context.New(config.Project{
+			Dist: dist,
+			GoMod: config.GoMod{
+				Proxy: true,
+			},
+			Builds: []config.Build{
+				{
+					ID:     "foo",
+					Goos:   []string{runtime.GOOS},
+					Goarch: []string{runtime.GOARCH},
+					Main:   "main.go",
+				},
+			},
+		})
+		ctx.Git.CurrentTag = "v0.161.1"
+
+		mod := "github.com/goreleaser/goreleaser"
+
+		fakeGoModAndSum(t, mod)
+		require.NoError(t, Pipe{}.Default(ctx))
+		require.NoError(t, Pipe{}.Run(ctx))
+		requireGoMod(t, mod, ctx.Git.CurrentTag)
+		requireMainGo(t, mod)
+		require.Equal(t, mod, ctx.Config.Builds[0].Main)
+		require.Equal(t, filepath.Join(dist, "proxy", "foo"), ctx.Config.Builds[0].Dir)
+		require.Equal(t, mod, ctx.ModulePath)
+	})
 }
 
 func requireGoMod(tb testing.TB, module, version string) {

www/docs/customization/build.md

@@ -24,8 +24,10 @@ builds:
     dir: go
 
     # Path to main.go file or main package.
+    # Notice: when used with `gomod.proxy`, this must be a package.
+    #
     # Default is `.`.
-    main: ./cmd/main.go
+    main: ./cmd/my-app
 
     # Binary name.
     # Can be a path (e.g. `bin/app`) to wrap the binary in a directory.
@@ -134,7 +136,7 @@ Here is an example with multiple binaries:
 ```yaml
 # .goreleaser.yml
 builds:
-  - main: ./cmd/cli/cli.go
+  - main: ./cmd/cli
     id: "cli"
     binary: cli
     goos:
@@ -142,7 +144,7 @@ builds:
       - darwin
       - windows
 
-  - main: ./cmd/worker/worker.go
+  - main: ./cmd/worker
     id: "worker"
     binary: worker
     goos:
@@ -150,7 +152,7 @@ builds:
       - darwin
       - windows
 
-  - main: ./cmd/tracker/tracker.go
+  - main: ./cmd/tracker
     id: "tracker"
     binary: tracker
     goos:

www/docs/customization/gomod.md

@@ -15,6 +15,7 @@ Configuration options available are described bellow.
 gomod:
   # Proxy a module from proxy.golang.org, making the builds verifiable.
   # This will only be effective if running against a tag. Snapshots will ignore this setting.
+  # PS: for this to work you `build.main` must be a package, not a `.go` file.
   #
   # Default is false.
   proxy: true