Adds configuration option to enable all available rules (#521)

Adds configuration option to enable all available rules

Author: chavacava

README.md

@@ -240,6 +240,59 @@ warningCode = 0
   severity = "error"
 ```
 
+By default `revive` will enable only the linting rules that are named in the configuration file.
+For example, the previous configuration file makes `revive` to enable only _cyclomatic_ and _package-comments_ linting rules.
+
+To enable all available rules you need to add:
+
+```toml
+enableAllRules = true
+```
+
+This will enable all available rules no matter of what rules are named in the configuration file.
+
+To disable a rule, you simply mark it as disabled in the configuration.
+For example:
+
+```toml
+[rule.line-length-limit]
+    Disabled = true
+```
+When enabling all rules you still need/can provide specific configurations for rules.
+The following files is an example configuration were all rules are enabled, with exception to those that are explicitly disabled, and some rules are configured with particular arguments:
+
+```toml
+severity = "warning"
+confidence = 0.8
+errorCode = 0
+warningCode = 0
+
+# Enable all available rules
+enableAllRules = true
+
+# Disabled rules
+[rule.blank-imports]
+    Disabled = true
+[rule.file-header]
+    Disabled = true
+[rule.max-public-structs]
+    Disabled = true
+[rule.line-length-limit]
+    Disabled = true
+[rule.function-length]
+    Disabled = true
+
+# Rule tunning
+[rule.argument-limit]
+    Arguments = [5]
+[rule.cyclomatic]    
+    Arguments = [10]
+[rule.cognitive-complexity]    
+    Arguments = [7]
+[rule.function-result-limit]    
+    Arguments = [3]
+```
+
 ### Default Configuration
 
 The default configuration of `revive` can be found at `defaults.toml`. This will enable all rules available in `golint` and use their default configuration (i.e. the way they are hardcoded in `golint`).
@@ -541,4 +594,3 @@ REVIVE_FORCE_COLOR=1 revive -formatter friendly ./... | tee revive.log
 ## License
 
 MIT
-

config/config.go

@@ -101,19 +101,48 @@ func getFormatters() map[string]lint.Formatter {
 	return result
 }
 
-// GetLintingRules yields the linting rules activated in the configuration
+// GetLintingRules yields the linting rules that must be applied by the linter
 func GetLintingRules(config *lint.Config) ([]lint.Rule, error) {
+	if config.EnableAllRules {
+		return getAllRules(config)
+	}
+
+	return getEnabledRules(config)
+}
+
+// getAllRules yields the list of all available rules except those disabled by configuration
+func getAllRules(config *lint.Config) ([]lint.Rule, error) {
+	lintingRules := []lint.Rule{}
+	for _, r := range allRules {
+		ruleConf := config.Rules[r.Name()]
+		if ruleConf.Disabled {
+			continue // skip disabled rules
+		}
+
+		lintingRules = append(lintingRules, r)
+	}
+
+	return lintingRules, nil
+}
+
+// getEnabledRules yields the list of rules that are enabled by configuration
+func getEnabledRules(config *lint.Config) ([]lint.Rule, error) {
 	rulesMap := map[string]lint.Rule{}
 	for _, r := range allRules {
 		rulesMap[r.Name()] = r
 	}
 
 	lintingRules := []lint.Rule{}
-	for name := range config.Rules {
+	for name, ruleConfig := range config.Rules {
 		rule, ok := rulesMap[name]
 		if !ok {
 			return nil, fmt.Errorf("cannot find rule: %s", name)
 		}
+
+		if ruleConfig.Disabled {
+			continue // skip disabled rules
+		}
+
 		lintingRules = append(lintingRules, rule)
 	}
 

lint/config.go

@@ -7,6 +7,7 @@ type Arguments = []interface{}
 type RuleConfig struct {
 	Arguments Arguments
 	Severity  Severity
+	Disabled  bool
 }
 
 // RulesConfig defines the config for all rules.
@@ -25,6 +26,7 @@ type Config struct {
 	IgnoreGeneratedHeader bool `toml:"ignoreGeneratedHeader"`
 	Confidence            float64
 	Severity              Severity
+	EnableAllRules        bool             `toml:"enableAllRules"`
 	Rules                 RulesConfig      `toml:"rule"`
 	ErrorCode             int              `toml:"errorCode"`
 	WarningCode           int              `toml:"warningCode"`

rule/cyclomatic.go

@@ -17,6 +17,9 @@ type CyclomaticRule struct{}
 func (r *CyclomaticRule) Apply(file *lint.File, arguments lint.Arguments) []lint.Failure {
 	var failures []lint.Failure
 
+	if len(arguments) == 0 {
+		panic("not enough arguments for " + r.Name())
+	}
 	complexity, ok := arguments[0].(int64) // Alt. non panicking version
 	if !ok {
 		panic("invalid argument for cyclomatic complexity")

rule/max-public-structs.go

@@ -14,6 +14,9 @@ type MaxPublicStructsRule struct{}
 // Apply applies the rule to given file.
 func (r *MaxPublicStructsRule) Apply(file *lint.File, arguments lint.Arguments) []lint.Failure {
 	var failures []lint.Failure
+	if len(arguments) == 0 {
+		panic("not enough arguments for " + r.Name())
+	}
 
 	fileAst := file.AST
 	walker := &lintMaxPublicStructs{