Fix config bug where mockery crashes when package map is nil

Taskfile.yml

@@ -52,7 +52,7 @@ tasks:
 
   test:
     cmds:
-      - go test -v -coverprofile=coverage.txt ./...
+      - go run gotest.tools/gotestsum --format testname -- -v -coverprofile=coverage.txt ./...
     desc: run unit tests
     sources:
       - "**/*.go"

cmd/showconfig.go

@@ -37,6 +37,11 @@ func showConfig(
 	if err != nil {
 		return stackerr.NewStackErrf(err, "failed to unmarshal config")
 	}
+	log, err := logging.GetLogger(config.LogLevel)
+	if err != nil {
+		return fmt.Errorf("getting logger: %w", err)
+	}
+	ctx = log.WithContext(ctx)
 	if err := config.Initialize(ctx); err != nil {
 		return err
 	}
@@ -48,10 +53,7 @@ func showConfig(
 	if err != nil {
 		return stackerr.NewStackErrf(err, "failed to marshal yaml")
 	}
-	log, err := logging.GetLogger(config.LogLevel)
-	if err != nil {
-		panic(err)
-	}
+
 	log.Info().Msgf("Using config: %s", config.Config)
 
 	fmt.Fprintf(outputter, "%s", string(out))

pkg/config/config.go

@@ -195,7 +195,14 @@ func (c *Config) GetPackages(ctx context.Context) ([]string, error) {
 	return packageList, nil
 }
 
+// getPackageConfigMap returns the map for the particular package, which includes
+// (but is not limited to) both the `configs` section and the `interfaces` section.
+// Note this does NOT return the `configs` section for the package. It returns the
+// entire mapping for the package.
 func (c *Config) getPackageConfigMap(ctx context.Context, packageName string) (map[string]any, error) {
+	log := zerolog.Ctx(ctx)
+	log.Trace().Msg("getting package config map")
+
 	cfgMap, err := c.CfgAsMap(ctx)
 	if err != nil {
 		return nil, err
@@ -207,13 +214,27 @@ func (c *Config) getPackageConfigMap(ctx context.Context, packageName string) (m
 	}
 	configAsMap, isMap := configUnmerged.(map[string]any)
 	if isMap {
+		log.Trace().Msg("package's value is a map, returning")
 		return configAsMap, nil
 	}
-	return map[string]any{}, nil
+	log.Trace().Msg("package's value is not a map")
+
+	// Package is something other than map, so set its value to an
+	// empty map.
+	emptyMap := map[string]any{}
+	packageSection[packageName] = emptyMap
+	return emptyMap, nil
 
 }
+
+// GetPackageConfig returns a struct representation of the package's config
+// as provided in yaml. If the package did not specify a config section,
+// this method will inject the top-level config into the package's config.
+// This is especially useful as it allows us to lazily evaluate a package's
+// config. If the package does specify config, this method takes care to merge
+// the top-level config with the values specified for this package.
 func (c *Config) GetPackageConfig(ctx context.Context, packageName string) (*Config, error) {
-	log := zerolog.Ctx(ctx)
+	log := zerolog.Ctx(ctx).With().Str("package-path", packageName).Logger()
 
 	if c.pkgConfigCache == nil {
 		log.Debug().Msg("package cache is nil")
@@ -223,11 +244,10 @@ func (c *Config) GetPackageConfig(ctx context.Context, packageName string) (*Con
 		return pkgConf, nil
 	}
 
-	pkgConfig := reflect.New(reflect.ValueOf(c).Elem().Type()).Interface()
+	pkgConfig := &Config{}
 	if err := copier.Copy(pkgConfig, c); err != nil {
 		return nil, fmt.Errorf("failed to copy config: %w", err)
 	}
-	pkgConfigTyped := pkgConfig.(*Config)
 
 	configMap, err := c.getPackageConfigMap(ctx, packageName)
 	if err != nil {
@@ -237,18 +257,24 @@ func (c *Config) GetPackageConfig(ctx context.Context, packageName string) (*Con
 	configSection, ok := configMap["config"]
 	if !ok {
 		log.Debug().Msg("config section not provided for package")
-		return pkgConfigTyped, nil
+		configMap["config"] = map[string]any{}
+		c.pkgConfigCache[packageName] = pkgConfig
+		return pkgConfig, nil
 	}
 
-	decoder, err := c.getDecoder(pkgConfigTyped)
+	// We know that the package specified config that is overriding the top-level
+	// config. We use a mapstructure decoder to decode the values in the yaml
+	// into the pkgConfig struct. This has the effect of merging top-level
+	// config with package-level config.
+	decoder, err := c.getDecoder(pkgConfig)
 	if err != nil {
 		return nil, stackerr.NewStackErrf(err, "failed to get decoder")
 	}
 	if err := decoder.Decode(configSection); err != nil {
 		return nil, err
 	}
-	c.pkgConfigCache[packageName] = pkgConfigTyped
-	return pkgConfigTyped, nil
+	c.pkgConfigCache[packageName] = pkgConfig
+	return pkgConfig, nil
 }
 
 func (c *Config) ExcludePath(path string) bool {
@@ -347,16 +373,15 @@ func (c *Config) GetInterfaceConfig(ctx context.Context, packageName string, int
 	}
 
 	// Copy the package-level config to our interface-level config
-	pkgConfigCopy := reflect.New(reflect.ValueOf(pkgConfig).Elem().Type()).Interface()
+	pkgConfigCopy := &Config{}
 	if err := copier.Copy(pkgConfigCopy, pkgConfig); err != nil {
 		return nil, stackerr.NewStackErrf(err, "failed to create a copy of package config")
 	}
-	baseConfigTyped := pkgConfigCopy.(*Config)
 
 	interfaceSection, ok := interfacesSection[interfaceName]
 	if !ok {
 		log.Debug().Msg("interface not defined in package configuration")
-		return []*Config{baseConfigTyped}, nil
+		return []*Config{pkgConfigCopy}, nil
 	}
 
 	interfaceSectionTyped, ok := interfaceSection.(map[string]any)
@@ -365,7 +390,7 @@ func (c *Config) GetInterfaceConfig(ctx context.Context, packageName string, int
 		// the interface but not provide any additional config beyond what
 		// is provided at the package level
 		if reflect.ValueOf(&interfaceSection).Elem().IsZero() {
-			return []*Config{baseConfigTyped}, nil
+			return []*Config{pkgConfigCopy}, nil
 		}
 		msgString := "bad type provided for interface config"
 		log.Error().Msgf(msgString)
@@ -376,11 +401,11 @@ func (c *Config) GetInterfaceConfig(ctx context.Context, packageName string, int
 	if ok {
 		log.Debug().Msg("config section exists for interface")
 		// if `config` is provided, we'll overwrite the values in our
-		// baseConfigTyped struct to act as the "new" base config.
+		// pkgConfigCopy struct to act as the "new" base config.
 		// This will allow us to set the default values for the interface
 		// but override them further for each mock defined in the
 		// `configs` section.
-		decoder, err := c.getDecoder(baseConfigTyped)
+		decoder, err := c.getDecoder(pkgConfigCopy)
 		if err != nil {
 			return nil, stackerr.NewStackErrf(err, "unable to create mapstructure decoder")
 		}
@@ -397,8 +422,8 @@ func (c *Config) GetInterfaceConfig(ctx context.Context, packageName string, int
 		configsSectionTyped := configsSection.([]any)
 		for _, configMap := range configsSectionTyped {
 			// Create a copy of the package-level config
-			currentInterfaceConfig := reflect.New(reflect.ValueOf(baseConfigTyped).Elem().Type()).Interface()
-			if err := copier.Copy(currentInterfaceConfig, baseConfigTyped); err != nil {
+			currentInterfaceConfig := reflect.New(reflect.ValueOf(pkgConfigCopy).Elem().Type()).Interface()
+			if err := copier.Copy(currentInterfaceConfig, pkgConfigCopy); err != nil {
 				return nil, stackerr.NewStackErrf(err, "failed to copy package config")
 			}
 
@@ -418,7 +443,7 @@ func (c *Config) GetInterfaceConfig(ctx context.Context, packageName string, int
 	log.Debug().Msg("configs section doesn't exist for interface")
 
 	if len(configs) == 0 {
-		configs = append(configs, baseConfigTyped)
+		configs = append(configs, pkgConfigCopy)
 	}
 	return configs, nil
 }
@@ -429,31 +454,33 @@ func (c *Config) addSubPkgConfig(ctx context.Context, subPkgPath string, parentP
 	log := zerolog.Ctx(ctx).With().
 		Str("parent-package", parentPkgPath).
 		Str("sub-package", subPkgPath).Logger()
+	ctx = log.WithContext(ctx)
 
-	log.Trace().Msg("adding sub-package to config map")
+	log.Debug().Msg("adding sub-package to config map")
 	parentPkgConfig, err := c.getPackageConfigMap(ctx, parentPkgPath)
 	if err != nil {
 		log.Err(err).
 			Msg("failed to get package config for parent package")
 		return fmt.Errorf("failed to get package config: %w", err)
 	}
 
-	log.Trace().Msg("getting config")
-	cfg, err := c.CfgAsMap(ctx)
+	log.Debug().Msg("getting config")
+	topLevelConfig, err := c.CfgAsMap(ctx)
 	if err != nil {
 		return fmt.Errorf("failed to get configuration map: %w", err)
 	}
 
-	log.Trace().Msg("getting packages section")
-	packagesSection := cfg["packages"].(map[string]any)
+	log.Debug().Msg("getting packages section")
+	packagesSection := topLevelConfig["packages"].(map[string]any)
 
-	// Don't overwrite any config that already exists
 	_, pkgExists := packagesSection[subPkgPath]
 	if !pkgExists {
 		log.Trace().Msg("sub-package doesn't exist in config")
+
+		// Copy the parent package directly into the subpackage config section
 		packagesSection[subPkgPath] = map[string]any{}
 		newPkgSection := packagesSection[subPkgPath].(map[string]any)
-		newPkgSection["config"] = parentPkgConfig["config"]
+		newPkgSection["config"] = deepCopyConfigMap(parentPkgConfig["config"].(map[string]any))
 	} else {
 		log.Trace().Msg("sub-package exists in config")
 		// The sub-package exists in config. Check if it has its
@@ -465,10 +492,15 @@ func (c *Config) addSubPkgConfig(ctx context.Context, subPkgPath string, parentP
 			log.Err(err).Msg("could not get child package config")
 			return fmt.Errorf("failed to get sub-package config: %w", err)
 		}
-
-		for key, val := range parentPkgConfig {
-			if _, keyInSubPkg := subPkgConfig[key]; !keyInSubPkg {
-				subPkgConfig[key] = val
+		log.Trace().Msgf("sub-package config: %v", subPkgConfig)
+		log.Trace().Msgf("parent-package config: %v", parentPkgConfig)
+
+		// Merge the parent config with the sub-package config.
+		parentConfigSection := parentPkgConfig["config"].(map[string]any)
+		subPkgConfigSection := subPkgConfig["config"].(map[string]any)
+		for key, val := range parentConfigSection {
+			if _, keyInSubPkg := subPkgConfigSection[key]; !keyInSubPkg {
+				subPkgConfigSection[key] = val
 			}
 
 		}
@@ -595,18 +627,24 @@ func (c *Config) subPackages(
 // recursive and recurses the file tree to find all sub-packages.
 func (c *Config) discoverRecursivePackages(ctx context.Context) error {
 	log := zerolog.Ctx(ctx)
+	log.Trace().Msg("discovering recursive packages")
 	recursivePackages := map[string]*Config{}
 	packageList, err := c.GetPackages(ctx)
 	if err != nil {
 		return fmt.Errorf("failed to get packages: %w", err)
 	}
 	for _, pkg := range packageList {
 		pkgConfig, err := c.GetPackageConfig(ctx, pkg)
+		pkgLog := log.With().Str("package", pkg).Logger()
+		pkgLog.Trace().Msg("iterating over package")
 		if err != nil {
 			return fmt.Errorf("failed to get package config: %w", err)
 		}
 		if pkgConfig.Recursive {
+			pkgLog.Trace().Msg("package marked as recursive")
 			recursivePackages[pkg] = pkgConfig
+		} else {
+			pkgLog.Trace().Msg("package not marked as recursive")
 		}
 	}
 	if len(recursivePackages) == 0 {
@@ -658,6 +696,17 @@ func contains[T comparable](slice []T, elem T) bool {
 	return false
 }
 
+func deepCopyConfigMap(src map[string]any) map[string]any {
+	newMap := map[string]any{}
+	for key, val := range src {
+		if contains([]string{"packages", "config", "interfaces"}, key) {
+			continue
+		}
+		newMap[key] = val
+	}
+	return newMap
+}
+
 // mergeInConfig takes care of merging inheritable configuration
 // in the config map. For example, it merges default config, then
 // package-level config, then interface-level config.
@@ -677,34 +726,62 @@ func (c *Config) mergeInConfig(ctx context.Context) error {
 	}
 	for _, pkgPath := range pkgs {
 		pkgLog := log.With().Str("package-path", pkgPath).Logger()
+		pkgCtx := pkgLog.WithContext(ctx)
+
 		pkgLog.Trace().Msg("merging for package")
-		packageConfig, err := c.getPackageConfigMap(ctx, pkgPath)
+		packageConfig, err := c.getPackageConfigMap(pkgCtx, pkgPath)
 		if err != nil {
 			pkgLog.Err(err).Msg("failed to get package config")
 			return fmt.Errorf("failed to get package config: %w", err)
 		}
+		pkgLog.Trace().Msgf("got package config map: %v", packageConfig)
+
 		configSectionUntyped, configExists := packageConfig["config"]
 		if !configExists {
-			packageConfig["config"] = defaultCfg
-			continue
+			// The reason why this should never happen is because getPackageConfigMap
+			// should be populating the config section with the top-level config if it
+			// wasn't defined in the yaml.
+			msg := "config section does not exist for package, this should never happen"
+			pkgLog.Error().Msg(msg)
+			return fmt.Errorf(msg)
+		}
+
+		pkgLog.Trace().Msg("got config section for package")
+		// Sometimes the config section may be provided, but it's nil.
+		// We need to account for this fact.
+		if configSectionUntyped == nil {
+			pkgLog.Trace().Msg("config section is nil, converting to empty map")
+			emptyMap := map[string]any{}
+
+			// We need to add this to the "global" config mapping so the change
+			// gets persisted, and also into configSectionUntyped for the logic
+			// further down.
+			packageConfig["config"] = emptyMap
+			configSectionUntyped = emptyMap
+		} else {
+			pkgLog.Trace().Msg("config section is not nil")
 		}
-		packageConfigSection := configSectionUntyped.(map[string]any)
+
+		configSectionTyped := configSectionUntyped.(map[string]any)
 
 		for key, value := range defaultCfg {
 			if contains([]string{"packages", "config"}, key) {
 				continue
 			}
-			_, keyExists := packageConfigSection[key]
+			keyValLog := pkgLog.With().Str("key", key).Str("value", fmt.Sprintf("%v", value)).Logger()
+
+			_, keyExists := configSectionTyped[key]
 			if !keyExists {
-				packageConfigSection[key] = value
+				keyValLog.Trace().Msg("setting key to value")
+				configSectionTyped[key] = value
 			}
 		}
-		interfaces, err := c.getInterfacesForPackage(ctx, pkgPath)
+		interfaces, err := c.getInterfacesForPackage(pkgCtx, pkgPath)
 		if err != nil {
 			return fmt.Errorf("failed to get interfaces for package: %w", err)
 		}
 		for _, interfaceName := range interfaces {
-			interfacesSection, err := c.getInterfacesSection(ctx, pkgPath)
+			interfacesSection, err := c.getInterfacesSection(pkgCtx, pkgPath)
 			if err != nil {
 				return err
 			}
@@ -728,7 +805,7 @@ func (c *Config) mergeInConfig(ctx context.Context) error {
 				// Assume this interface's value in the map is nil. Just skip it.
 				continue
 			}
-			for key, value := range packageConfigSection {
+			for key, value := range configSectionTyped {
 				if key == "packages" {
 					continue
 				}