refactor: debug/tracel logging improvements in js+orion generate+import (#116)

### Changes are visible to end-users: no

### Test plan

- Covered by existing test cases

Author: jbedard

language/js/resolve.go

@@ -42,7 +42,7 @@ func (*typeScriptLang) Name() string { return LanguageName }
 // Determine what rule (r) outputs which can be imported.
 // For TypeScript this is all the import-paths pointing to files within the rule.
 func (ts *typeScriptLang) Imports(c *config.Config, r *rule.Rule, f *rule.File) []resolve.ImportSpec {
-	BazelLog.Debugf("Imports(%s): //%s:%s", LanguageName, f.Pkg, r.Name())
+	BazelLog.Tracef("Imports(%s): //%s:%s", LanguageName, f.Pkg, r.Name())
 
 	switch r.Kind() {
 	case TsProtoLibraryKind:
@@ -63,12 +63,16 @@ func (ts *typeScriptLang) sourceFileImports(c *config.Config, r *rule.Rule, f *r
 
 	infoAttr := r.PrivateAttr("ts_project_info")
 	if infoAttr != nil && infoAttr.(*TsProjectInfo).sources != nil {
+		BazelLog.Debugf("Imports(%s): //%s:%s (generated %s)", LanguageName, f.Pkg, r.Name(), r.Kind())
+
 		srcsSet := infoAttr.(*TsProjectInfo).sources
 		srcs = make([]string, 0, srcsSet.Size())
 		for it := srcsSet.Iterator(); it.Next(); {
 			srcs = append(srcs, it.Value().(string))
 		}
 	} else {
+		BazelLog.Debugf("Imports(%s): //%s:%s (non-generated %s)", LanguageName, f.Pkg, r.Name(), r.Kind())
+
 		sourceFiles, err := common.GetSourceRegularFiles(f.Pkg)
 		if err != nil {
 			BazelLog.Errorf("Failed to fetch source files %s:%s - %v", f.Pkg, r.Name(), err)
@@ -124,6 +128,8 @@ func (ts *typeScriptLang) sourceFileImports(c *config.Config, r *rule.Rule, f *r
 }
 
 func (ts *typeScriptLang) tsconfigImports(r *rule.Rule, f *rule.File) []resolve.ImportSpec {
+	BazelLog.Debugf("Imports(%s): //%s:%s (%s)", LanguageName, f.Pkg, r.Name(), r.Kind())
+
 	// Only the tsconfig file itself is exposed.
 	// The output is the same as the ts_config(src) input.
 	return []resolve.ImportSpec{
@@ -143,6 +149,8 @@ func (ts *typeScriptLang) protoLibraryImports(r *rule.Rule, f *rule.File) []reso
 		return nil
 	}
 
+	BazelLog.Debugf("Imports(%s): //%s:%s (%s)", LanguageName, f.Pkg, r.Name(), r.Kind())
+
 	protoSrcs := protoSrcsAttr.([]string)
 	dtsOutputs := []string{}
 

language/orion/resolver.go

@@ -46,8 +46,6 @@ const extGeneratedRules = "__starzelle_generated_rules"
 const extGeneratedRulesPkg = "__starzelle_generated_rules_pkg"
 
 func (re *GazelleHost) importsGenerateRules(cfg *BUILDConfig, c *config.Config, f *rule.File) gazelleLanguage.GenerateResult {
-	BazelLog.Debugf("Imports.GenerateRules(%s): //%s", GazelleLanguageName, f.Pkg)
-
 	regularFiles, err := common.GetSourceRegularFiles(f.Pkg)
 	if err != nil {
 		BazelLog.Fatalf("Error getting regular files for %s: %v", f.Pkg, err)
@@ -61,58 +59,62 @@ func (re *GazelleHost) importsGenerateRules(cfg *BUILDConfig, c *config.Config,
 
 		// The RegularFiles are processed by the GazelleHost and passed to plugins.
 		RegularFiles: regularFiles,
-
-		// Subdirs and GenFiles are not used by the GazelleHost, just pass empty slices.
-		Subdirs:  []string{},
-		GenFiles: []string{},
-
-		// OtherEmpty and OtherGen are not used by the GazelleHost, just pass empty slices.
-		OtherEmpty: []*rule.Rule{},
-		OtherGen:   []*rule.Rule{},
 	})
 }
 
 // Determine what rule (r) outputs which can be imported.
 func (re *GazelleHost) Imports(c *config.Config, r *rule.Rule, f *rule.File) []resolve.ImportSpec {
-	BazelLog.Debugf("Imports(%s): //%s:%s", GazelleLanguageName, f.Pkg, r.Name())
+	BazelLog.Tracef("Imports(%s): //%s:%s", GazelleLanguageName, f.Pkg, r.Name())
+
+	// This rule was generated by this gazelle extension.
+	if declaration := r.PrivateAttr(targetDeclarationKey); declaration != nil {
+		BazelLog.Debugf("Imports(%s): //%s:%s (generated %s)", GazelleLanguageName, f.Pkg, r.Name(), r.Kind())
+		return symbolToImportSpecList(declaration.(plugin.TargetDeclaration).Symbols)
+	}
 
 	cfg := getBUILDConfig(c, f.Pkg)
 
-	// If GenerateRules() was not run by gazelle
-	if !cfg.generated {
-		// With GazelleHost the Imports() functionality is provided at rule generation time, not
-		// a separate Import-extraction phase.
-		//
-		// When running partial generations this means we must manually invoke GenerateRules() if it
-		// was not invoked by gazelle as part of the partial run.
-		if c.Exts[extGeneratedRulesPkg] != cfg.rel {
-			c.Exts[extGeneratedRules] = re.importsGenerateRules(cfg, c, f)
-			c.Exts[extGeneratedRulesPkg] = cfg.rel
-		}
+	// Generation was done for this package, but this rule was not one of them.
+	if cfg.generated {
+		return nil
+	}
 
-		// Find this rule in the host-generated rules
-		genResult := c.Exts[extGeneratedRules].(gazelleLanguage.GenerateResult)
-		for _, genRule := range genResult.Gen {
-			if genRule.Kind() == r.Kind() && genRule.Name() == r.Name() {
-				r = genRule
-				break
-			}
-		}
+	// Otherwise generation was not done for this package and must be manually invoked.
+	//
+	// With GazelleHost the Imports() functionality is provided at rule generation time, not
+	// a separate Import-extraction phase.
+	//
+	// When running partial generations this means we must manually invoke GenerateRules() if it
+	// was not invoked by gazelle as part of the partial run.
+	if c.Exts[extGeneratedRulesPkg] != f.Pkg {
+		BazelLog.Debugf("Imports.GenerateRules(%s): //%s", GazelleLanguageName, f.Pkg)
+		c.Exts[extGeneratedRules] = re.importsGenerateRules(cfg, c, f)
+		c.Exts[extGeneratedRulesPkg] = f.Pkg
 	}
 
-	targetDeclarationAttr := r.PrivateAttr(targetDeclarationKey)
-	if targetDeclarationAttr == nil {
-		// This rule was not generated by this gazelle extension.
-		return nil
+	// Find this rule in the host-generated rules
+	genResult := c.Exts[extGeneratedRules].(gazelleLanguage.GenerateResult)
+	for _, g := range genResult.Gen {
+		if g.Kind() == r.Kind() && g.Name() == r.Name() {
+			// TODO: what if the rule generation is different and not what is expected?
+			// ... it is possible this directory is not being updated, and if it were updated
+			// the result would be different.
+			if declaration := g.PrivateAttr(targetDeclarationKey); declaration != nil {
+				BazelLog.Debugf("Imports(%s): //%s:%s (not generated %s)", GazelleLanguageName, f.Pkg, g.Name(), g.Kind())
+				return symbolToImportSpecList(declaration.(plugin.TargetDeclaration).Symbols)
+			}
+			break
+		}
 	}
 
-	targetDeclaration := targetDeclarationAttr.(plugin.TargetDeclaration)
+	return nil
+}
 
-	res := make([]resolve.ImportSpec, 0, len(targetDeclaration.Symbols))
-	for _, s := range targetDeclaration.Symbols {
+func symbolToImportSpecList(symbols []plugin.Symbol) []resolve.ImportSpec {
+	res := make([]resolve.ImportSpec, 0, len(symbols))
+	for _, s := range symbols {
 		res = append(res, symbolToImportSpec(s))
 	}
-
 	return res
 }