[Analyze] Support compile commands with relative paths (realm#3501)

* [Analyze] Support compile commands with relative paths

* Add changelog entry

And made small formatting edits to other recent entries.

CHANGELOG.md

@@ -21,11 +21,14 @@
 
 #### Enhancements
 
-* None.
+* Support relative paths in compilation databases for SwiftLint analyzer
+  rules.  
+  [JP Simard](https://github.com/jpsim)
 
 #### Bug Fixes
 
-* Fix `custom_rules` merging when the parent configuration is based on `only_rules`.  
+* Fix `custom_rules` merging when the parent configuration is based on
+  `only_rules`.  
   [Frederick Pietschmann](https://github.com/fredpi)
   [#3468](https://github.com/realm/SwiftLint/issues/3468)
 
@@ -34,7 +37,8 @@
   [Frederick Pietschmann](https://github.com/fredpi)
   [#3472](https://github.com/realm/SwiftLint/issues/3472)
 
-* Fix bug that prevented the reconfiguration of a custom rule in a child config.  
+* Fix bug that prevented the reconfiguration of a custom rule in a child
+  config.  
   [Frederick Pietschmann](https://github.com/fredpi)
   [#3477](https://github.com/realm/SwiftLint/issues/3477)
 

Source/swiftlint/Helpers/LintableFilesVisitor.swift

@@ -16,7 +16,8 @@ enum CompilerInvocations {
                 return CompilerArgumentsExtractor
                     .compilerArgumentsForFile(path, compilerInvocations: compilerInvocations)
             case let .compilationDatabase(compileCommands):
-                return compileCommands[path]
+                return compileCommands[path] ??
+                    compileCommands[path.path(relativeTo: FileManager.default.currentDirectoryPath)]
             }
         } ?? []
     }