chore: fix source of truth for generate when doing releases (#3509)

Currently when running generate after bumping versions, it was reading
directly from librarian.yaml (which wasn't updated with the latest
version) so cargo.toml and readme files were not getting updated.
Instead of writing to disk every time for every library, I updated the
logic to use the generate function that takes in the config object.
However generate updates the config object, so we need to pass in a
clone so the original object doesn't get modified, as we write it back
to librarian.yaml at the end of release with updated versions.

I do think this can be reworked but in order to be ready for tuesday's
release I am proposing this fix and will open separate ticket to
refactor when time allows.

Author: ldetmer

internal/librarian/release.go

@@ -16,6 +16,7 @@ package librarian
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"strings"
@@ -90,8 +91,16 @@ func runRelease(ctx context.Context, cmd *cli.Command) error {
 		return err
 	}
 
+	if cfg.Sources == nil || cfg.Sources.Googleapis == nil {
+		return errNoGoogleapiSourceInfo
+	}
+	googleapisDir, err := fetchSource(ctx, cfg.Sources.Googleapis, googleapisRepo)
+	if err != nil {
+		return err
+	}
+
 	if all {
-		if err = releaseAll(ctx, cfg, lastTag, gitExe); err != nil {
+		if err = releaseAll(ctx, cfg, lastTag, gitExe, googleapisDir); err != nil {
 			return err
 		}
 	} else {
@@ -103,14 +112,14 @@ func runRelease(ctx context.Context, cmd *cli.Command) error {
 		if err != nil {
 			return err
 		}
-		if err = releaseLibrary(ctx, cfg, libConfg, libConfg.Output, lastTag, gitExe); err != nil {
+		if err = releaseLibrary(ctx, cfg, libConfg, libConfg.Output, lastTag, gitExe, googleapisDir); err != nil {
 			return err
 		}
 	}
 	return RunTidyOnConfig(ctx, cfg)
 }
 
-func releaseAll(ctx context.Context, cfg *config.Config, lastTag, gitExe string) error {
+func releaseAll(ctx context.Context, cfg *config.Config, lastTag, gitExe, googleapisDir string) error {
 	filesChanged, err := git.FilesChangedSince(ctx, lastTag, gitExe, cfg.Release.IgnoredChanges)
 	if err != nil {
 		return err
@@ -121,7 +130,7 @@ func releaseAll(ctx context.Context, cfg *config.Config, lastTag, gitExe string)
 			return err
 		}
 		if shouldRelease(library, filesChanged, library.Output) {
-			if err := releaseLibrary(ctx, cfg, library, library.Output, lastTag, gitExe); err != nil {
+			if err := releaseLibrary(ctx, cfg, library, library.Output, lastTag, gitExe, googleapisDir); err != nil {
 				return err
 			}
 		}
@@ -145,7 +154,7 @@ func shouldRelease(library *config.Library, filesChanged []string, srcPath strin
 	return false
 }
 
-func releaseLibrary(ctx context.Context, cfg *config.Config, libConfig *config.Library, srcPath, lastTag, gitExe string) error {
+func releaseLibrary(ctx context.Context, cfg *config.Config, libConfig *config.Library, srcPath, lastTag, gitExe, googleapisDir string) error {
 	switch cfg.Language {
 	case languageFake:
 		return fakeReleaseLibrary(libConfig)
@@ -160,7 +169,14 @@ func releaseLibrary(ctx context.Context, cfg *config.Config, libConfig *config.L
 		if err := rust.ReleaseLibrary(libConfig, srcPath); err != nil {
 			return err
 		}
-		if err := runGenerate(ctx, false, libConfig.Name); err != nil {
+		copyConfig, err := cloneConfig(cfg)
+		if err != nil {
+			return err
+		}
+		if _, err := generateLibrary(ctx, copyConfig, googleapisDir, libConfig.Name); err != nil {
+			return err
+		}
+		if err := formatLibrary(ctx, cfg.Language, libConfig); err != nil {
 			return err
 		}
 		return nil
@@ -181,3 +197,15 @@ func libraryByName(c *config.Config, name string) (*config.Library, error) {
 	}
 	return nil, errLibraryNotFound
 }
+
+func cloneConfig(orig *config.Config) (*config.Config, error) {
+	data, err := json.Marshal(orig)
+	if err != nil {
+		return nil, err
+	}
+	var copy config.Config
+	if err := json.Unmarshal(data, &copy); err != nil {
+		return nil, err
+	}
+	return &copy, nil
+}

internal/librarian/release_test.go

@@ -278,7 +278,7 @@ func TestRelease(t *testing.T) {
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
 			libConfg := &config.Library{}
-			err := releaseLibrary(t.Context(), cfg, libConfg, test.srcPath, test.lastTag, "git")
+			err := releaseLibrary(t.Context(), cfg, libConfg, test.srcPath, test.lastTag, "git", "")
 			if err != nil {
 				t.Fatalf("releaseLibrary() error = %v", err)
 			}
@@ -349,7 +349,7 @@ func TestReleaseAll(t *testing.T) {
 			}
 			remoteDir := testhelper.SetupRepoWithChange(t, tag)
 			testhelper.CloneRepository(t, remoteDir)
-			err := releaseAll(t.Context(), config, tag, "git")
+			err := releaseAll(t.Context(), config, tag, "git", "")
 			if err != nil {
 				t.Fatal(err)
 			}