feat: add support for enforce-repeated-arg-type-style rule (#953)

README.md

@@ -537,6 +537,7 @@ List of all available rules. The rules ported from `golint` are left unchanged a
 | [`import-alias-naming`](./RULES_DESCRIPTIONS.md#import-alias-naming) | string or map[string]string (defaults to allow regex pattern ^[a-z][a-z0-9]{0,}$) | Conventions around the naming of import aliases. | no | no |
 | [`enforce-map-style`](./RULES_DESCRIPTIONS.md#enforce-map-style) | string (defaults to "any") | Enforces consistent usage of `make(map[type]type)` or `map[type]type{}` for map initialization. Does not affect `make(map[type]type, size)` constructions. | no | no |
 | [`enforce-slice-style`](./RULES_DESCRIPTIONS.md#enforce-slice-style) | string (defaults to "any") | Enforces consistent usage of `make([]type, 0)` or `[]type{}` for slice initialization. Does not affect `make(map[type]type, non_zero_len, or_non_zero_cap)` constructions. | no | no |
+| [`enforce-repeated-arg-type-style`](./RULES_DESCRIPTIONS.md#enforce-repeated-arg-type-style) | string (defaults to "any") | Enforces consistent style for repeated argument and/or return value types. | no | no |
 
 
 ## Configurable rules

RULES_DESCRIPTIONS.md

@@ -386,6 +386,44 @@ Example:
  arguments = ["make"]
 ```
 
+
+## enforce-repeated-arg-type-style
+
+**Description**: This rule is designed to maintain consistency in the declaration
+of repeated argument and return value types in Go functions. It supports three styles:
+'any', 'short', and 'full'. The 'any' style is lenient and allows any form of type
+declaration. The 'short' style encourages omitting repeated types for conciseness,
+whereas the 'full' style mandates explicitly stating the type for each argument
+and return value, even if they are repeated, promoting clarity.
+
+**Configuration (1)**: (string) as a single string, it configures both argument
+and return value styles. Accepts 'any', 'short', or 'full' (default: 'any').
+
+**Configuration (2)**: (map[string]any) as a map, allows separate configuration
+for function arguments and return values. Valid keys are "funcArgStyle" and
+"funcRetValStyle", each accepting 'any', 'short', or 'full'. If a key is not
+specified, the default value of 'any' is used.
+
+**Note**: The rule applies checks based on the specified styles. For 'full' style,
+it flags instances where types are omitted in repeated arguments or return values.
+For 'short' style, it highlights opportunities to omit repeated types for brevity.
+Incorrect or unknown configuration values will result in an error.
+
+**Example (1)**:
+
+```toml
+[rule.enforce-repeated-arg-type-style]
+arguments = ["short"]
+```
+
+**Example (2):**
+
+```toml
+[rule.enforce-repeated-arg-type-style]
+arguments = [ { funcArgStyle = "full", funcRetValStyle = "short" } ]
+```
+
+
 ## enforce-slice-style
 
 _Description_: This rule enforces consistent usage of `make([]type, 0)` or `[]type{}` for slice initialization.
@@ -499,7 +537,8 @@ _Description_: Aligns with Go's naming conventions, as outlined in the official
 the principles of good package naming. Users can follow these guidelines by default or define a custom regex rule.
 Importantly, aliases with underscores ("_") are always allowed.
 
-_Configuration_ (1): (string) as plain string accepts allow regexp pattern for aliases (default: ^[a-z][a-z0-9]{0,}$),
+_Configuration_ (1): (string) as plain string accepts allow regexp pattern for aliases (default: ^[a-z][a-z0-9]{0,}$).
+
 _Configuration_ (2): (map[string]string) as a map accepts two values:
 * for a key "allowRegex" accepts allow regexp pattern
 * for a key "denyRegex deny regexp pattern

rule/enforce-repeated-arg-type-style.go

@@ -0,0 +1,191 @@
+package rule
+
+import (
+ "fmt"
+ "go/ast"
+ "go/types"
+ "sync"
+
+ "github.com/mgechev/revive/lint"
+)
+
+type enforceRepeatedArgTypeStyleType string
+
+const (
+ enforceRepeatedArgTypeStyleTypeAny enforceRepeatedArgTypeStyleType = "any"
+ enforceRepeatedArgTypeStyleTypeShort enforceRepeatedArgTypeStyleType = "short"
+ enforceRepeatedArgTypeStyleTypeFull enforceRepeatedArgTypeStyleType = "full"
+)
+
+func repeatedArgTypeStyleFromString(s string) enforceRepeatedArgTypeStyleType {
+ switch s {
+ case string(enforceRepeatedArgTypeStyleTypeAny), "":
+ return enforceRepeatedArgTypeStyleTypeAny
+ case string(enforceRepeatedArgTypeStyleTypeShort):
+ return enforceRepeatedArgTypeStyleTypeShort
+ case string(enforceRepeatedArgTypeStyleTypeFull):
+ return enforceRepeatedArgTypeStyleTypeFull
+ default:
+ err := fmt.Errorf(
+ "invalid repeated arg type style: %s (expecting one of %v)",
+ s,
+ []enforceRepeatedArgTypeStyleType{
+ enforceRepeatedArgTypeStyleTypeAny,
+ enforceRepeatedArgTypeStyleTypeShort,
+ enforceRepeatedArgTypeStyleTypeFull,
+ },
+ )
+
+ panic(fmt.Sprintf("Invalid argument to the enforce-repeated-arg-type-style rule: %v", err))
+ }
+}
+
+// EnforceRepeatedArgTypeStyleRule implements a rule to enforce repeated argument type style.
+type EnforceRepeatedArgTypeStyleRule struct {
+ configured bool
+ funcArgStyle enforceRepeatedArgTypeStyleType
+ funcRetValStyle enforceRepeatedArgTypeStyleType
+
+ sync.Mutex
+}
+
+func (r *EnforceRepeatedArgTypeStyleRule) configure(arguments lint.Arguments) {
+ r.Lock()
+ defer r.Unlock()
+
+ if r.configured {
+ return
+ }
+ r.configured = true
+
+ r.funcArgStyle = enforceRepeatedArgTypeStyleTypeAny
+ r.funcRetValStyle = enforceRepeatedArgTypeStyleTypeAny
+
+ if len(arguments) == 0 {
+ return
+ }
+
+ switch funcArgStyle := arguments[0].(type) {
+ case string:
+ r.funcArgStyle = repeatedArgTypeStyleFromString(funcArgStyle)
+ r.funcRetValStyle = repeatedArgTypeStyleFromString(funcArgStyle)
+ case map[string]any: // expecting map[string]string
+ for k, v := range funcArgStyle {
+ switch k {
+ case "funcArgStyle":
+ val, ok := v.(string)
+ if !ok {
+ panic(fmt.Sprintf("Invalid map value type for 'enforce-repeated-arg-type-style' rule. Expecting string, got %T", v))
+ }
+ r.funcArgStyle = repeatedArgTypeStyleFromString(val)
+ case "funcRetValStyle":
+ val, ok := v.(string)
+ if !ok {
+ panic(fmt.Sprintf("Invalid map value '%v' for 'enforce-repeated-arg-type-style' rule. Expecting string, got %T", v, v))
+ }
+ r.funcRetValStyle = repeatedArgTypeStyleFromString(val)
+ default:
+ panic(fmt.Sprintf("Invalid map key for 'enforce-repeated-arg-type-style' rule. Expecting 'funcArgStyle' or 'funcRetValStyle', got %v", k))
+ }
+ }
+ default:
+ panic(fmt.Sprintf("Invalid argument '%v' for 'import-alias-naming' rule. Expecting string or map[string]string, got %T", arguments[0], arguments[0]))
+ }
+}
+
+// Apply applies the rule to a given file.
+func (r *EnforceRepeatedArgTypeStyleRule) Apply(file *lint.File, arguments lint.Arguments) []lint.Failure {
+ r.configure(arguments)
+
+ if r.funcArgStyle == enforceRepeatedArgTypeStyleTypeAny && r.funcRetValStyle == enforceRepeatedArgTypeStyleTypeAny {
+ // This linter is not configured, return no failures.
+ return nil
+ }
+
+ var failures []lint.Failure
+
+ err := file.Pkg.TypeCheck()
+ if err != nil {
+ // the file has other issues
+ return nil
+ }
+ typesInfo := file.Pkg.TypesInfo()
+
+ astFile := file.AST
+ ast.Inspect(astFile, func(n ast.Node) bool {
+ switch fn := n.(type) {
+ case *ast.FuncDecl:
+ if r.funcArgStyle == enforceRepeatedArgTypeStyleTypeFull {
+ if fn.Type.Params != nil {
+ for _, field := range fn.Type.Params.List {
+ if len(field.Names) > 1 {
+ failures = append(failures, lint.Failure{
+ Confidence: 1,
+ Node: field,
+ Category: "style",
+ Failure: "argument types should not be omitted",
+ })
+ }
+ }
+ }
+ }
+
+ if r.funcArgStyle == enforceRepeatedArgTypeStyleTypeShort {
+ var prevType ast.Expr
+ if fn.Type.Params != nil {
+ for _, field := range fn.Type.Params.List {
+ if types.Identical(typesInfo.Types[field.Type].Type, typesInfo.Types[prevType].Type) {
+ failures = append(failures, lint.Failure{
+ Confidence: 1,
+ Node: field,
+ Category: "style",
+ Failure: "repeated argument type can be omitted",
+ })
+ }
+ prevType = field.Type
+ }
+ }
+ }
+
+ if r.funcRetValStyle == enforceRepeatedArgTypeStyleTypeFull {
+ if fn.Type.Results != nil {
+ for _, field := range fn.Type.Results.List {
+ if len(field.Names) > 1 {
+ failures = append(failures, lint.Failure{
+ Confidence: 1,
+ Node: field,
+ Category: "style",
+ Failure: "return types should not be omitted",
+ })
+ }
+ }
+ }
+ }
+
+ if r.funcRetValStyle == enforceRepeatedArgTypeStyleTypeShort {
+ var prevType ast.Expr
+ if fn.Type.Results != nil {
+ for _, field := range fn.Type.Results.List {
+ if field.Names != nil && types.Identical(typesInfo.Types[field.Type].Type, typesInfo.Types[prevType].Type) {
+ failures = append(failures, lint.Failure{
+ Confidence: 1,
+ Node: field,
+ Category: "style",
+ Failure: "repeated return type can be omitted",
+ })
+ }
+ prevType = field.Type
+ }
+ }
+ }
+ }
+ return true
+ })
+
+ return failures
+}
+
+// Name returns the name of the linter rule.
+func (*EnforceRepeatedArgTypeStyleRule) Name() string {
+ return "enforce-repeated-arg-type-style"
+}

test/enforce-repeated-arg-type-style_test.go

@@ -0,0 +1,123 @@
+package test
+
+import (
+ "testing"
+
+ "github.com/mgechev/revive/lint"
+ "github.com/mgechev/revive/rule"
+)
+
+func TestEnforceRepeatedArgTypeStyleShort(t *testing.T) {
+ testRule(t, "enforce-repeated-arg-type-style-short-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{"short"},
+ })
+ testRule(t, "enforce-repeated-arg-type-style-short-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{"short"},
+ })
+
+ testRule(t, "enforce-repeated-arg-type-style-short-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `short`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-short-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcRetValStyle": `short`,
+ },
+ },
+ })
+}
+
+func TestEnforceRepeatedArgTypeStyleFull(t *testing.T) {
+ testRule(t, "enforce-repeated-arg-type-style-full-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{"full"},
+ })
+ testRule(t, "enforce-repeated-arg-type-style-full-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{"full"},
+ })
+
+ testRule(t, "enforce-repeated-arg-type-style-full-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `full`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-full-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcRetValStyle": `full`,
+ },
+ },
+ })
+}
+
+func TestEnforceRepeatedArgTypeStyleMixed(t *testing.T) {
+ testRule(t, "enforce-repeated-arg-type-style-full-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `full`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-full-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `full`,
+ "funcRetValStyle": `any`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-full-args", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `full`,
+ "funcRetValStyle": `short`,
+ },
+ },
+ })
+
+ testRule(t, "enforce-repeated-arg-type-style-full-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcRetValStyle": `full`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-full-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `any`,
+ "funcRetValStyle": `full`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-full-return", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `short`,
+ "funcRetValStyle": `full`,
+ },
+ },
+ })
+
+ testRule(t, "enforce-repeated-arg-type-style-mixed-full-short", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `full`,
+ "funcRetValStyle": `short`,
+ },
+ },
+ })
+ testRule(t, "enforce-repeated-arg-type-style-mixed-short-full", &rule.EnforceRepeatedArgTypeStyleRule{}, &lint.RuleConfig{
+ Arguments: []any{
+ map[string]any{
+ "funcArgStyle": `short`,
+ "funcRetValStyle": `full`,
+ },
+ },
+ })
+}