Merge pull request #298 from JanTvrdik/pr/manual_code_coverage_save

Allow manually save partial code coverage to free memory

src/CodeCoverage/Collector.php

@@ -16,6 +16,18 @@ class Collector
 	/** @var resource */
 	private static $file;
 
+	/** @var string */
+	private static $collector;
+
+
+	/**
+	 * @return bool
+	 */
+	public static function isStarted()
+	{
+		return self::$file !== NULL;
+	}
+
 
 	/**
 	 * Starts gathering the information for code coverage.
@@ -24,33 +36,55 @@ class Collector
 	 */
 	public static function start($file)
 	{
-		if (self::$file) {
+		if (self::isStarted()) {
 			throw new \LogicException('Code coverage collector has been already started.');
 		}
-		self::$file = fopen($file, 'a+');
+		self::$file = fopen($file, 'c+');
 
 		if (defined('PHPDBG_VERSION') && PHP_VERSION_ID >= 70000) {
 			phpdbg_start_oplog();
-			$collector = 'collectPhpDbg';
+			self::$collector = 'collectPhpDbg';
 
 		} elseif (extension_loaded('xdebug')) {
 			xdebug_start_code_coverage(XDEBUG_CC_UNUSED | XDEBUG_CC_DEAD_CODE);
-			$collector = 'collectXdebug';
+			self::$collector = 'collectXdebug';
 
 		} else {
 			$alternative = PHP_VERSION_ID >= 70000 ? ' or phpdbg SAPI' : '';
 			throw new \Exception("Code coverage functionality requires Xdebug extension$alternative.");
 		}
 
-		register_shutdown_function(function () use ($collector) {
-			register_shutdown_function(function () use ($collector) {
-				list($positive, $negative) = call_user_func([__CLASS__, $collector]);
-				self::save($positive, $negative);
-			});
+		register_shutdown_function(function () {
+			register_shutdown_function([__CLASS__, 'save']);
 		});
 	}
 
 
+	/**
+	 * Saves information about code coverage. Can be called repeatedly to free memory.
+	 * @return void
+	 */
+	public static function save()
+	{
+		list($positive, $negative) = call_user_func([__CLASS__, self::$collector]);
+
+		flock(self::$file, LOCK_EX);
+		fseek(self::$file, 0);
+		$rawContent = stream_get_contents(self::$file);
+		$original = $rawContent ? unserialize($rawContent) : [];
+		$coverage = array_replace_recursive($negative, $original, $positive);
+
+		fseek(self::$file, 0);
+		ftruncate(self::$file, 0);
+		fwrite(self::$file, serialize($coverage));
+		flock(self::$file, LOCK_UN);
+
+		if (self::$collector === 'collectPhpDbg') {
+			phpdbg_start_oplog();
+		}
+	}
+
+
 	/**
 	 * Collects information about code coverage.
 	 * @return array
@@ -97,21 +131,4 @@ private static function collectPhpDbg()
 		return [$positive, $negative];
 	}
 
-
-	/**
-	 * Saves information about code coverage. Do not call directly.
-	 * @return void
-	 */
-	private static function save(array $positive, array $negative)
-	{
-		flock(self::$file, LOCK_EX);
-		fseek(self::$file, 0);
-		$original = @unserialize(stream_get_contents(self::$file)) ?: []; // @ file may be empty
-		$coverage = array_replace_recursive($negative, $original, $positive);
-
-		ftruncate(self::$file, 0);
-		fwrite(self::$file, serialize($coverage));
-		fclose(self::$file);
-	}
-
 }

tests/CodeCoverage/Collector.phpt

@@ -0,0 +1,40 @@
+<?php
+
+use Tester\Assert;
+use Tester\CodeCoverage;
+use Tester\FileMock;
+
+require __DIR__ . '/../bootstrap.php';
+
+
+if (!extension_loaded('xdebug') && (!defined('PHPDBG_VERSION') || PHP_VERSION_ID < 70000)) {
+	Tester\Environment::skip('Requires Xdebug or phpdbg SAPI.');
+}
+
+if (CodeCoverage\Collector::isStarted()) {
+	Tester\Environment::skip('Requires running without --coverage.');
+}
+
+$outputFile = FileMock::create('');
+
+Assert::false(CodeCoverage\Collector::isStarted());
+CodeCoverage\Collector::start($outputFile);
+Assert::true(CodeCoverage\Collector::isStarted());
+
+Assert::exception(function () use ($outputFile) {
+	CodeCoverage\Collector::start($outputFile);
+}, 'LogicException', 'Code coverage collector has been already started.');
+
+$content = file_get_contents($outputFile);
+Assert::same('', $content);
+
+CodeCoverage\Collector::save();
+$coverage = unserialize(file_get_contents($outputFile));
+Assert::type('array', $coverage);
+Assert::same(1, $coverage[__FILE__][__LINE__ - 3]); // line with 1st Collector::save()
+
+CodeCoverage\Collector::save(); // save() can be called repeatedly
+$coverage = unserialize(file_get_contents($outputFile));
+Assert::type('array', $coverage);
+Assert::same(1, $coverage[__FILE__][__LINE__ - 8]); // line with 1st Collector::save()
+Assert::same(1, $coverage[__FILE__][__LINE__ - 4]); // line with 2nd Collector::save()