Fix bad replacement pattern parse

$n wasn't interpreted correctly when it was at the end of a pattern.
ltrzesniewski · May 7, 2019 · 327f19f · 327f19f
1 parent 72a3158
commit 327f19f
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Showing 2 changed files with 49 additions and 17 deletions.
diff --git a/src/PCRE.NET.Tests/PcreNet/ReplaceTests.cs b/src/PCRE.NET.Tests/PcreNet/ReplaceTests.cs
@@ -24,6 +24,42 @@ public void should_replace_matches_with_pattern()
             Assert.That(result, Is.EqualTo("foo <aabb><bb><aabb> bar <aaabb><bb><aaabb><ab><b><ab> baz"));
         }
 
+        [Test]
+        public void should_replace_indexed_groups_with_braces()
+        {
+            var re = new PcreRegex(@"a+(?<grp>b+)", PcreOptions.IgnoreCase);
+            var result = re.Replace("foo aabb bar aaabbab baz", "<${1}>");
+
+            Assert.That(result, Is.EqualTo("foo <bb> bar <bb><b> baz"));
+        }
+
+        [Test]
+        public void should_replace_indexed_groups_without_braces()
+        {
+            var re = new PcreRegex(@"a+(?<grp>b+)", PcreOptions.IgnoreCase);
+            var result = re.Replace("foo aabb bar aaabbab baz", "<$1>");
+
+            Assert.That(result, Is.EqualTo("foo <bb> bar <bb><b> baz"));
+        }
+
+        [Test]
+        public void should_replace_indexed_groups_with_braces_at_end_of_pattern()
+        {
+            var re = new PcreRegex(@"a+(?<grp>b+)", PcreOptions.IgnoreCase);
+            var result = re.Replace("foo aabb bar aaabbab baz", "#${1}");
+
+            Assert.That(result, Is.EqualTo("foo #bb bar #bb#b baz"));
+        }
+
+        [Test]
+        public void should_replace_indexed_groups_without_braces_at_end_of_pattern()
+        {
+            var re = new PcreRegex(@"a+(?<grp>b+)", PcreOptions.IgnoreCase);
+            var result = re.Replace("foo aabb bar aaabbab baz", "#$1");
+
+            Assert.That(result, Is.EqualTo("foo #bb bar #bb#b baz"));
+        }
+
         [Test]
         public void should_replace_named_groups()
         {

diff --git a/src/PCRE.NET/Internal/ReplacementPattern.cs b/src/PCRE.NET/Internal/ReplacementPattern.cs
@@ -106,15 +106,11 @@ public static Func<PcreMatch, string> Parse(string replacementPattern)
 
                             var fallback = new LiteralPart(replacementPattern, startIdx - 1, idx - startIdx + 1);
 
-                            if (idx < replacementPattern.Length)
+                            var groupIndexString = replacementPattern.Substring(startIdx, idx - startIdx);
+                            if (int.TryParse(groupIndexString, NumberStyles.None, CultureInfo.InvariantCulture, out var groupIndex))
                             {
-                                var groupIndexString = replacementPattern.Substring(startIdx, idx - startIdx);
-                                int groupIndex;
-                                if (Int32.TryParse(groupIndexString, NumberStyles.None, CultureInfo.InvariantCulture, out groupIndex))
-                                {
-                                    parts.Add(new IndexedGroupPart(groupIndex, fallback));
-                                    break;
-                                }
+                                parts.Add(new IndexedGroupPart(groupIndex, fallback));
+                                break;
                             }
 
                             parts.Add(fallback);
@@ -174,10 +170,10 @@ public LiteralPart(string text, int startIndex, int length)
                 _length = length;
             }
 
-            public override void Append(PcreMatch match, StringBuilder sb) 
+            public override void Append(PcreMatch match, StringBuilder sb)
                 => sb.Append(_text, _startIndex, _length);
 
-            public override string ToString() 
+            public override string ToString()
                 => $"Literal: {_text.Substring(_startIndex, _length)}";
         }
 
@@ -243,18 +239,18 @@ public override void Append(PcreMatch match, StringBuilder sb)
                     sb.Append(match.Subject, group.Index, group.Length);
             }
 
-            public override string ToString() 
+            public override string ToString()
                 => $"Group: {_name}";
         }
 
         private sealed class PreMatchPart : ReplacementPart
         {
             public static readonly PreMatchPart Instance = new PreMatchPart();
 
-            public override void Append(PcreMatch match, StringBuilder sb) 
+            public override void Append(PcreMatch match, StringBuilder sb)
                 => sb.Append(match.Subject, 0, match.Index);
 
-            public override string ToString() 
+            public override string ToString()
                 => "Pre match";
         }
 
@@ -268,18 +264,18 @@ public override void Append(PcreMatch match, StringBuilder sb)
                 sb.Append(match.Subject, endOfMatch, match.Subject.Length - endOfMatch);
             }
 
-            public override string ToString() 
+            public override string ToString()
                 => "Post match";
         }
 
         private sealed class FullInputPart : ReplacementPart
         {
             public static readonly FullInputPart Instance = new FullInputPart();
 
-            public override void Append(PcreMatch match, StringBuilder sb) 
+            public override void Append(PcreMatch match, StringBuilder sb)
                 => sb.Append(match.Subject);
 
-            public override string ToString() 
+            public override string ToString()
                 => "Full input";
         }
 
@@ -300,7 +296,7 @@ public override void Append(PcreMatch match, StringBuilder sb)
                 }
             }
 
-            public override string ToString() 
+            public override string ToString()
                 => "Last matched group";
         }
     }