fix(lint/js): improve diagnostics for noConstantCondition, useForOf, noRedeclare (#9889)

Author: dyc3

.changeset/clear-bananas-lie.md

@@ -0,0 +1,5 @@
+---
+"@biomejs/biome": patch
+---
+
+Improved the diagnostics for [`useForOf`](https://biomejs.dev/linter/rules/use-for-of/) to better explain the problem, why it matters, and how to fix it.

.changeset/plain-keys-arrive.md

@@ -0,0 +1,5 @@
+---
+"@biomejs/biome": patch
+---
+
+Improved the diagnostics for [`noConstantCondition`](https://biomejs.dev/linter/rules/no-constant-condition/) to better explain the problem, why it matters, and how to fix it.

.changeset/yellow-fans-glow.md

@@ -0,0 +1,5 @@
+---
+"@biomejs/biome": patch
+---
+
+Improved the diagnostics for [`noRedeclare`](https://biomejs.dev/linter/rules/no-redeclare/) to better explain the problem, why it matters, and how to fix it.

crates/biome_cli/tests/snapshots/main_cases_handle_astro_files/full_support.snap

@@ -184,7 +184,7 @@ file.astro:41:1 lint/a11y/useHtmlLang ━━━━━━━━━━━━━━
 ```block
 file.astro:11:6 lint/suspicious/noRedeclare ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 
-  × Shouldn't redeclare 'Props'. Consider to delete it or rename it.
+  × 'Props' is redeclared in the same scope.
   
      9 │ }
     10 │ 
@@ -201,13 +201,17 @@ file.astro:11:6 lint/suspicious/noRedeclare ━━━━━━━━━━━━
     8 │ 	name: string;
     9 │ }
   
+  i Redeclarations make it unclear which variable a reference points to and can hide earlier declarations.
+  
+  i Remove the duplicate declaration or rename one of the variables.
+  
 
 ```
 
 ```block
 file.astro:30:7 lint/suspicious/noRedeclare ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 
-  × Shouldn't redeclare 'Props'. Consider to delete it or rename it.
+  × 'Props' is redeclared in the same scope.
   
     28 │ 	}
     29 │ 
@@ -225,6 +229,10 @@ file.astro:30:7 lint/suspicious/noRedeclare ━━━━━━━━━━━━
     27 │ 		name: string;
     28 │ 	}
   
+  i Redeclarations make it unclear which variable a reference points to and can hide earlier declarations.
+  
+  i Remove the duplicate declaration or rename one of the variables.
+  
 
 ```
 

crates/biome_cli/tests/snapshots/main_cases_reporter_checkstyle/reports_diagnostics_checkstyle_check_command.snap

@@ -56,8 +56,8 @@ check ━━━━━━━━━━━━━━━━━━━━━━━━
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
     <error line="0" column="0" severity="error" message="Formatter would have printed the following content:" source="format" />
   </file>
   <file name="main.ts">
@@ -70,8 +70,8 @@ check ━━━━━━━━━━━━━━━━━━━━━━━━
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
     <error line="0" column="0" severity="error" message="Formatter would have printed the following content:" source="format" />
   </file>
 </checkstyle>

crates/biome_cli/tests/snapshots/main_cases_reporter_checkstyle/reports_diagnostics_checkstyle_check_command_file.snap

@@ -17,8 +17,8 @@ expression: redactor(content)
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
     <error line="0" column="0" severity="error" message="Formatter would have printed the following content:" source="format" />
   </file>
   <file name="main.ts">
@@ -31,8 +31,8 @@ expression: redactor(content)
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
     <error line="0" column="0" severity="error" message="Formatter would have printed the following content:" source="format" />
   </file>
 </checkstyle>

crates/biome_cli/tests/snapshots/main_cases_reporter_checkstyle/reports_diagnostics_checkstyle_ci_command.snap

@@ -56,8 +56,8 @@ ci ━━━━━━━━━━━━━━━━━━━━━━━━━
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
     <error line="0" column="0" severity="error" message="File content differs from formatting output" source="format" />
   </file>
   <file name="main.ts">
@@ -70,8 +70,8 @@ ci ━━━━━━━━━━━━━━━━━━━━━━━━━
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
     <error line="0" column="0" severity="error" message="File content differs from formatting output" source="format" />
   </file>
 </checkstyle>

crates/biome_cli/tests/snapshots/main_cases_reporter_checkstyle/reports_diagnostics_checkstyle_lint_command.snap

@@ -55,8 +55,8 @@ lint ━━━━━━━━━━━━━━━━━━━━━━━━━
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
   </file>
   <file name="main.ts">
     <error line="1" column="8" severity="warning" message="This import is unused." source="lint/correctness/noUnusedImports" />
@@ -67,8 +67,8 @@ lint ━━━━━━━━━━━━━━━━━━━━━━━━━
     <error line="6" column="1" severity="error" message="This is an unexpected use of the debugger statement." source="lint/suspicious/noDebugger" />
     <error line="8" column="5" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
     <error line="9" column="7" severity="error" message="This variable implicitly has the any type." source="lint/suspicious/noImplicitAnyLet" />
-    <error line="2" column="10" severity="error" message="Shouldn&apos;t redeclare &apos;z&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
-    <error line="9" column="7" severity="error" message="Shouldn&apos;t redeclare &apos;f&apos;. Consider to delete it or rename it." source="lint/suspicious/noRedeclare" />
+    <error line="2" column="10" severity="error" message="&apos;z&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
+    <error line="9" column="7" severity="error" message="&apos;f&apos; is redeclared in the same scope." source="lint/suspicious/noRedeclare" />
   </file>
 </checkstyle>
 

crates/biome_cli/tests/snapshots/main_cases_reporter_github/reports_diagnostics_github_check_command.snap

@@ -96,11 +96,11 @@ check ━━━━━━━━━━━━━━━━━━━━━━━━
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=index.ts,line=2,endLine=2,col=10,endColumn=11::Shouldn't redeclare 'z'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=index.ts,line=2,endLine=2,col=10,endColumn=11::'z' is redeclared in the same scope.
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=index.ts,line=9,endLine=9,col=7,endColumn=8::Shouldn't redeclare 'f'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=index.ts,line=9,endLine=9,col=7,endColumn=8::'f' is redeclared in the same scope.
 ```
 
 ```block
@@ -128,11 +128,11 @@ check ━━━━━━━━━━━━━━━━━━━━━━━━
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=main.ts,line=2,endLine=2,col=10,endColumn=11::Shouldn't redeclare 'z'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=main.ts,line=2,endLine=2,col=10,endColumn=11::'z' is redeclared in the same scope.
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=main.ts,line=9,endLine=9,col=7,endColumn=8::Shouldn't redeclare 'f'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=main.ts,line=9,endLine=9,col=7,endColumn=8::'f' is redeclared in the same scope.
 ```
 
 ```block

crates/biome_cli/tests/snapshots/main_cases_reporter_github/reports_diagnostics_github_ci_command.snap

@@ -96,11 +96,11 @@ ci ━━━━━━━━━━━━━━━━━━━━━━━━━
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=index.ts,line=2,endLine=2,col=10,endColumn=11::Shouldn't redeclare 'z'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=index.ts,line=2,endLine=2,col=10,endColumn=11::'z' is redeclared in the same scope.
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=index.ts,line=9,endLine=9,col=7,endColumn=8::Shouldn't redeclare 'f'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=index.ts,line=9,endLine=9,col=7,endColumn=8::'f' is redeclared in the same scope.
 ```
 
 ```block
@@ -128,11 +128,11 @@ ci ━━━━━━━━━━━━━━━━━━━━━━━━━
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=main.ts,line=2,endLine=2,col=10,endColumn=11::Shouldn't redeclare 'z'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=main.ts,line=2,endLine=2,col=10,endColumn=11::'z' is redeclared in the same scope.
 ```
 
 ```block
-::error title=lint/suspicious/noRedeclare,file=main.ts,line=9,endLine=9,col=7,endColumn=8::Shouldn't redeclare 'f'. Consider to delete it or rename it.
+::error title=lint/suspicious/noRedeclare,file=main.ts,line=9,endLine=9,col=7,endColumn=8::'f' is redeclared in the same scope.
 ```
 
 ```block