feature #31546 [Dotenv] Use default value when referenced variable is not set (j92)

xabbuh · xabbuh · commit 2070e30018bb · 2019-08-06T09:27:26.000+02:00
This PR was squashed before being merged into the 4.4 branch (closes #31546). Discussion ---------- [Dotenv] Use default value when referenced variable is not set | Q | A | ------------- | --- | Branch? | 4.4 | Bug fix? | no | New feature? | yes  | BC breaks? | no  | Deprecations? | no  | Tests pass? | yes  | Fixed tickets | #...  | License | MIT | Doc PR | symfony/symfony-docs#11956  In bash you have the option to define a default variable like this: ```bash FOO=${VARIABLE:-default} ``` When VARIABLE is not set ```bash FOO=${VARIABLE:-default} #FOO=default ``` When VARIABLE is set: ```bash VARIABLE=test FOO=${VARIABLE:-default} #FOO=test ``` If others find this also a good idea, I will write documentation and add the Doc PR. But first I would like some feedback to check if anyone agrees with this feature. Commits ------- 790dbad [Dotenv] Use default value when referenced variable is not set
diff --git a/src/Symfony/Component/Dotenv/Dotenv.php b/src/Symfony/Component/Dotenv/Dotenv.php
@@ -432,6 +432,7 @@ private function resolveVariables(string $value)
             (?!\()                             # no opening parenthesis
             (?P<opening_brace>\{)?             # optional brace
             (?P<name>'.self::VARNAME_REGEX.')? # var name
+            (?P<default_value>:-[^\}]++)?      # optional default value
             (?P<closing_brace>\})?             # optional closing brace
         /x';
 
@@ -461,6 +462,15 @@ private function resolveVariables(string $value)
                 $value = (string) getenv($name);
             }
 
+            if ('' === $value && isset($matches['default_value'])) {
+                $unsupportedChars = strpbrk($matches['default_value'], '\'"{$');
+                if (false !== $unsupportedChars) {
+                    throw $this->createFormatException(sprintf('Unsupported character "%s" found in the default value of variable "$%s".', $unsupportedChars[0], $name));
+                }
+
+                $value = substr($matches['default_value'], 2);
+            }
+
             if (!$matches['opening_brace'] && isset($matches['closing_brace'])) {
                 $value .= '}';
             }
diff --git a/src/Symfony/Component/Dotenv/Tests/DotenvTest.php b/src/Symfony/Component/Dotenv/Tests/DotenvTest.php
@@ -48,6 +48,9 @@ public function getEnvDataWithFormatErrors()
             ['FOO!', "Missing = in the environment variable declaration in \".env\" at line 1.\n...FOO!...\n     ^ line 1 offset 3"],
             ['FOO=$(echo foo', "Missing closing parenthesis. in \".env\" at line 1.\n...FOO=$(echo foo...\n                ^ line 1 offset 14"],
             ['FOO=$(echo foo'."\n", "Missing closing parenthesis. in \".env\" at line 1.\n...FOO=$(echo foo\\n...\n                ^ line 1 offset 14"],
+            ["FOO=\nBAR=\${FOO:-\'a{a}a}", "Unsupported character \"'\" found in the default value of variable \"\$FOO\". in \".env\" at line 2.\n...\\nBAR=\${FOO:-\'a{a}a}...\n                       ^ line 2 offset 24"],
+            ["FOO=\nBAR=\${FOO:-a\$a}", "Unsupported character \"\$\" found in the default value of variable \"\$FOO\". in \".env\" at line 2.\n...FOO=\\nBAR=\${FOO:-a\$a}...\n                       ^ line 2 offset 20"],
+            ["FOO=\nBAR=\${FOO:-a\"a}", "Unclosed braces on variable expansion in \".env\" at line 2.\n...FOO=\\nBAR=\${FOO:-a\"a}...\n                    ^ line 2 offset 17"],
         ];
 
         if ('\\' !== \DIRECTORY_SEPARATOR) {
@@ -159,6 +162,10 @@ public function getEnvData()
             ['BAR=$REMOTE', ['BAR' => 'remote']],
             ['BAR=$SERVERVAR', ['BAR' => 'servervar']],
             ['FOO=$NOTDEFINED', ['FOO' => '']],
+            ["FOO=BAR\nBAR=\${FOO:-TEST}", ['FOO' => 'BAR', 'BAR' => 'BAR']],
+            ["FOO=BAR\nBAR=\${NOTDEFINED:-TEST}", ['FOO' => 'BAR', 'BAR' => 'TEST']],
+            ["FOO=\nBAR=\${FOO:-TEST}", ['FOO' => '', 'BAR' => 'TEST']],
+            ["FOO=\nBAR=\$FOO:-TEST}", ['FOO' => '', 'BAR' => 'TEST}']],
         ];
 
         if ('\\' !== \DIRECTORY_SEPARATOR) {
