From aa9d2de559c2fff735000e4733b0405652434ff4 Mon Sep 17 00:00:00 2001
From: Quan Tong <quantonganh@gmail.com>
Date: Mon, 6 Nov 2023 12:01:13 +0700
Subject: [PATCH] cmd/go: print the package containing the unmatched embed
 patterns

Fixes #49534

Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest,gotip-windows-amd64-longtest
Change-Id: Ia95868ecc1c3dc9715c0fdc7ab1f30348fffaef5
Reviewed-on: https://go-review.googlesource.com/c/go/+/540017
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
---
 src/cmd/go/internal/modcmd/vendor.go          | 47 ++++++++++++-------
 .../go/testdata/script/mod_vendor_embed.txt   |  8 +++-
 2 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/src/cmd/go/internal/modcmd/vendor.go b/src/cmd/go/internal/modcmd/vendor.go
index 3db85bda530..44e0439f687 100644
--- a/src/cmd/go/internal/modcmd/vendor.go
+++ b/src/cmd/go/internal/modcmd/vendor.go
@@ -324,7 +324,13 @@ func vendorPkg(vdir, pkg string) {
 	}
 	embeds, err := load.ResolveEmbed(bp.Dir, embedPatterns)
 	if err != nil {
-		base.Fatal(err)
+		format := "go: resolving embeds in %s: %v\n"
+		if vendorE {
+			fmt.Fprintf(os.Stderr, format, pkg, err)
+		} else {
+			base.Errorf(format, pkg, err)
+		}
+		return
 	}
 	for _, embed := range embeds {
 		embedDst := filepath.Join(dst, embed)
@@ -333,23 +339,30 @@ func vendorPkg(vdir, pkg string) {
 		}
 
 		// Copy the file as is done by copyDir below.
-		r, err := os.Open(filepath.Join(src, embed))
+		err := func() error {
+			r, err := os.Open(filepath.Join(src, embed))
+			if err != nil {
+				return err
+			}
+			if err := os.MkdirAll(filepath.Dir(embedDst), 0777); err != nil {
+				return err
+			}
+			w, err := os.Create(embedDst)
+			if err != nil {
+				return err
+			}
+			if _, err := io.Copy(w, r); err != nil {
+				return err
+			}
+			r.Close()
+			return w.Close()
+		}()
 		if err != nil {
-			base.Fatal(err)
-		}
-		if err := os.MkdirAll(filepath.Dir(embedDst), 0777); err != nil {
-			base.Fatal(err)
-		}
-		w, err := os.Create(embedDst)
-		if err != nil {
-			base.Fatal(err)
-		}
-		if _, err := io.Copy(w, r); err != nil {
-			base.Fatal(err)
-		}
-		r.Close()
-		if err := w.Close(); err != nil {
-			base.Fatal(err)
+			if vendorE {
+				fmt.Fprintf(os.Stderr, "go: %v\n", err)
+			} else {
+				base.Error(err)
+			}
 		}
 	}
 }
diff --git a/src/cmd/go/testdata/script/mod_vendor_embed.txt b/src/cmd/go/testdata/script/mod_vendor_embed.txt
index 1a3b2fef26d..4a27b1431fb 100644
--- a/src/cmd/go/testdata/script/mod_vendor_embed.txt
+++ b/src/cmd/go/testdata/script/mod_vendor_embed.txt
@@ -6,11 +6,15 @@ cmp vendor/example.com/a/subdir/test/xtest/embed.txt a/subdir/test/xtest/embed.t
 
 cd broken_no_matching_files
 ! go mod vendor
-stderr 'go: pattern foo.txt: no matching files found'
+stderr '^go: resolving embeds in example.com/brokendep: pattern foo.txt: no matching files found$'
+go mod vendor -e
+stderr '^go: resolving embeds in example.com/brokendep: pattern foo.txt: no matching files found$'
 
 cd ../broken_bad_pattern
 ! go mod vendor
-stderr 'go: pattern ../foo.txt: invalid pattern syntax'
+stderr '^go: resolving embeds in example.com/brokendep: pattern ../foo.txt: invalid pattern syntax$'
+go mod vendor -e
+stderr '^go: resolving embeds in example.com/brokendep: pattern ../foo.txt: invalid pattern syntax$'
 
 cd ../embed_go122
 go mod vendor