Expose source path on LogFileInterface

Add LogFileInterface::getPath(): ?string so detectors can dispatch on a
filename hint when the original path is known. Default implementation on
the abstract LogFile base returns null; PathLogFile records its
constructor argument. StringLogFile and StreamLogFile inherit the null
default. Tests cover both the path and null-fallback cases.

src/Log/File/LogFile.php

@@ -10,6 +10,7 @@ namespace IndifferentKetchup\Codex\Log\File;
 abstract class LogFile implements LogFileInterface
 {
     protected ?string $content = null;
+    protected ?string $path = null;
 
     /**
      * Get the log file content
@@ -20,4 +21,14 @@ abstract class LogFile implements LogFileInterface
     {
         return $this->content;
     }
+
+    /**
+     * Get the source path of the log file when one is known
+     *
+     * @return string|null
+     */
+    public function getPath(): ?string
+    {
+        return $this->path;
+    }
 }

src/Log/File/LogFileInterface.php

@@ -15,4 +15,15 @@ interface LogFileInterface
      * @return string
      */
     public function getContent(): string;
+
+    /**
+     * Get the source path of the log file when one is known
+     *
+     * Returns null for log files without a filesystem origin (string content,
+     * arbitrary streams). Concrete implementations should return the path used
+     * to construct them when applicable.
+     *
+     * @return string|null
+     */
+    public function getPath(): ?string;
 }

src/Log/File/PathLogFile.php

@@ -22,6 +22,7 @@ class PathLogFile extends LogFile
             throw new InvalidArgumentException("File '" . $path . "' not found.");
         }
 
+        $this->path = $path;
         $this->content = file_get_contents($path);
     }
 }

test/tests/Log/File/PathLogFileTest.php

@@ -14,4 +14,12 @@ class PathLogFileTest extends TestCase
 
         $this->assertStringEqualsFile($path, $logFile->getContent());
     }
+
+    public function testGetPathReturnsConstructorArgument(): void
+    {
+        $path = __DIR__ . "/../../../data/simple.log";
+        $logFile = new PathLogFile($path);
+
+        $this->assertSame($path, $logFile->getPath());
+    }
 }

test/tests/Log/File/StringLogFileTest.php

@@ -14,4 +14,11 @@ class StringLogFileTest extends TestCase
 
         $this->assertEquals($content, $logFile->getContent());
     }
+
+    public function testGetPathReturnsNull(): void
+    {
+        $logFile = new StringLogFile("anything");
+
+        $this->assertNull($logFile->getPath());
+    }
 }