Fix nested type constructors raising error

JakubValtar · JakubValtar · commit 4336026bfafd · 2016-11-16T01:36:20.000+01:00
Replace non-capturing groups by positive lookahead and lookbehind, because they don't consume the source String and allow for first and last group to overlap when two constructors are directly nested. Fixes processing#4652
diff --git a/java/src/processing/mode/java/pdex/SourceUtils.java b/java/src/processing/mode/java/pdex/SourceUtils.java
@@ -55,8 +55,12 @@ public static List<Edit> parseProgramImports(CharSequence source,
 
 
 
+  // Positive lookahead and lookbehind are needed to match all type constructors
+  // in code like `int(byte(245))` where first bracket matches as last
+  // group in "^int(" but also as a first group in "(byte(". Lookahead and
+  // lookbehind won't consume the shared character.
   public static final Pattern TYPE_CONSTRUCTOR_REGEX =
-      Pattern.compile("(?:^|\\W)(int|char|float|boolean|byte)(?:\\s*\\()",
+      Pattern.compile("(?<=^|\\W)(int|char|float|boolean|byte)(?=\\s*\\()",
                       Pattern.MULTILINE);
 
   public static List<Edit> replaceTypeConstructors(CharSequence source) {
