Split TrailingCommaRule (#1555)

Split rule `trailing-comma` into `trailing-comma-on-call-site` and `trailing-comma-on-declaration-site`

Co-authored-by: paul-dingemans <paul-dingemans@users.noreply.github.com>

CHANGELOG.md

@@ -131,6 +131,7 @@ The callback function provided as parameter to the format function is now called
 * Fix multiline if-statements `multiline-if-else` ([#828](https://github.com/pinterest/ktlint/issues/828))
 * Prevent class cast exception on ".editorconfig" property `ktlint_code_style`  ([#1559](https://github.com/pinterest/ktlint/issues/1559))
 * Handle trailing comma in enums `trailing-comma` ([#1542](https://github.com/pinterest/ktlint/pull/1542))
+* Split rule `trailing-comma` into `trailing-comma-on-call-site` and `trailing-comma-on-declaration-site` ([#1555](https://github.com/pinterest/ktlint/pull/1555))
 
 ### Changed
 

docs/faq.md

@@ -91,7 +91,7 @@ import package.b.*
 An error for a specific rule on a specific line can be disabled with a `@Suppress` annotation:
 
 ```kotlin
-@Suppress("ktlint:max-line-length","ktlint:experimental:trailing-comma")
+@Suppress("ktlint:max-line-length","ktlint:experimental:trailing-comma-on-call-site")
 val foo = listOf(
     "some really looooooooooooooooong string exceeding the max line length",
   )

docs/rules/configuration.md

@@ -176,18 +176,29 @@ max_line_length = -1 # Use "off" (or -1) to ignore max line length or a positive
 
 This setting is used by multiple rules of which rule `max-line-length` is the most important.
 
-## Trailing comma
+## Trailing comma on call site
 
-Trailing comma's (both on call and declaration site) are disabled (e.g. not allowed) by. When enabling the properties, the trailing becomes mandatory where applicable.
+By default, trailing comma's on call site are not allowed. When enabling the property, the trailing comma becomes mandatory where applicable.
 
 Example:
 ```ini
 [*.{kt,kts}]
-ij_kotlin_allow_trailing_comma = false
 ij_kotlin_allow_trailing_comma_on_call_site = false
 ```
 
-This setting only takes effect when rule `trailing-comma` is enabled.
+This setting only takes effect when rule `trailing-comma-on-call-site` is enabled.
+
+## Trailing comma on declaration site
+
+By default, trailing comma's on declaration site are not allowed. When enabling the property, the trailing comma becomes mandatory where applicable.
+
+Example:
+```ini
+[*.{kt,kts}]
+ij_kotlin_allow_trailing_comma = false # Only used for declaration site 
+```
+
+This setting only takes effect when rule `trailing-comma-on-declaration-site` is enabled.
 
 ## Overriding Editorconfig properties for specific directories
 

docs/rules/standard.md

@@ -106,7 +106,7 @@ When a line is broken at an assignment (`=`) operator the break comes after the
 
 Rule id: `no-line-break-before-assignment`
 
-## Nu multi spaces
+## No multi spaces
 
 Except in indentation and in KDoc's it is not allowed to have multiple consecutive spaces.
 
@@ -166,11 +166,17 @@ Consistent string templates (`$v` instead of `${v}`, `${p.v}` instead of `${p.v.
 
 Rule id: `string-template`
 
-## Trailing comma
+## Trailing comma on call site
 
-Consistent removal (default) or adding of trailing comma's (both on call and declaration site).
+Consistent removal (default) or adding of trailing comma's on call site.
 
-Rule id: `trailing-comma`
+Rule id: `trailing-comma-on-call-site`
+
+## Trailing comma on declaration site
+
+Consistent removal (default) or adding of trailing comma's on declaration site.
+
+Rule id: `trailing-comma-on-declaration-site`
 
 ## Spacing
 

ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/MaxLineLengthRule.kt

@@ -28,7 +28,15 @@ class MaxLineLengthRule :
                 // This rule should run after all other rules. Each time a rule visitor is modified with
                 // RunAsLateAsPossible, it needs to be checked that this rule still runs after that new rule or that it
                 // won't be affected by that rule.
-                ruleId = "trailing-comma",
+                ruleId = "trailing-comma-on-call-site",
+                loadOnlyWhenOtherRuleIsLoaded = false,
+                runOnlyWhenOtherRuleIsEnabled = false
+            ),
+            VisitorModifier.RunAfterRule(
+                // This rule should run after all other rules. Each time a rule visitor is modified with
+                // RunAsLateAsPossible, it needs to be checked that this rule still runs after that new rule or that it
+                // won't be affected by that rule.
+                ruleId = "trailing-comma-on-declaration-site",
                 loadOnlyWhenOtherRuleIsLoaded = false,
                 runOnlyWhenOtherRuleIsEnabled = false
             ),

ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/StandardRuleSetProvider.kt

@@ -2,7 +2,6 @@ package com.pinterest.ktlint.ruleset.standard
 
 import com.pinterest.ktlint.core.RuleProvider
 import com.pinterest.ktlint.core.RuleSetProviderV2
-import com.pinterest.ktlint.ruleset.experimental.trailingcomma.TrailingCommaRule
 
 public class StandardRuleSetProvider :
     RuleSetProviderV2(
@@ -59,7 +58,8 @@ public class StandardRuleSetProvider :
             RuleProvider { SpacingBetweenDeclarationsWithAnnotationsRule() },
             RuleProvider { SpacingBetweenDeclarationsWithCommentsRule() },
             RuleProvider { StringTemplateRule() },
-            RuleProvider { TrailingCommaRule() },
+            RuleProvider { TrailingCommaOnCallSiteRule() },
+            RuleProvider { TrailingCommaOnDeclarationSiteRule() },
             RuleProvider { WrappingRule() }
         )
 }