Fixes #59 elif and else compilation errors

exodrifter · Jan 24, 2018 · 5330e42 · 5330e42
1 parent 445a11e
commit 5330e42
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Showing 2 changed files with 129 additions and 39 deletions.
diff --git a/Editor/Tests/Language/CompilerTest.cs b/Editor/Tests/Language/CompilerTest.cs
@@ -181,6 +181,75 @@ public void CompileStatement()
 			Assert.IsAssignableFrom<MultiplyExpression>(
 				(nodes[0] as Statement).expression);
 		}
+
+		/// <summary>
+		/// Checks if 'if', 'elif', and 'else' statements compile.
+		/// <summary>
+		[Test]
+		public void CompileControlFlow()
+		{
+			var nodes = Compiler.Compile(@"
+if foo:
+	pause
+elif bar:
+	pause
+else:
+	pause
+");
+			Assert.AreEqual(1, nodes.Count);
+			Assert.IsAssignableFrom<Condition>(nodes[0]);
+
+			nodes = Compiler.Compile(@"
+if foo:
+	pause
+else:
+	pause
+");
+			Assert.AreEqual(1, nodes.Count);
+			Assert.IsAssignableFrom<Condition>(nodes[0]);
+
+			nodes = Compiler.Compile(@"
+if foo:
+	pause
+
+else:
+	pause
+");
+			Assert.AreEqual(1, nodes.Count);
+			Assert.IsAssignableFrom<Condition>(nodes[0]);
+
+			nodes = Compiler.Compile(@"
+if foo:
+	pause
+
+elif bar:
+	pause
+
+else:
+	pause
+");
+			Assert.AreEqual(1, nodes.Count);
+			Assert.IsAssignableFrom<Condition>(nodes[0]);
+
+			nodes = Compiler.Compile(@"
+if foo:
+	pause
+
+	
+elif bar:
+	pause
+
+   # comment
+elif car:
+	pause
+
+# comment
+else:
+	pause
+");
+			Assert.AreEqual(1, nodes.Count);
+			Assert.IsAssignableFrom<Condition>(nodes[0]);
+		}
 	}
 }
 

diff --git a/Language/Parser.cs b/Language/Parser.cs
@@ -221,6 +221,28 @@ private Reader GetTempOnNextLine(Reader reader)
 			return temp;
 		}
 
+		private Reader GetTempOnNextNonEmptyLine(Reader reader)
+		{
+			var temp = GetTempOnNextLine(reader);
+			while (!temp.EOF)
+			{
+				// Check if the line is not blank
+				try
+				{
+					GetTempOnNextLine(temp);
+				}
+				catch (UnusedException)
+				{
+					return temp;
+				}
+
+				// Keep reading
+				temp.NextLine();
+			}
+
+			return temp;
+		}
+
 		#endregion
 
 		#region Compile Commands
@@ -326,32 +348,30 @@ private Condition CompileIf(Reader reader, int depth)
 			reader.Expect(':');
 			var children = CompileChildren(reader, depth);
 
-			var temp = GetTempOnNextLine(reader);
+			var temp = GetTempOnNextNonEmptyLine(reader);
 			var nextDepth = temp.Skip();
+
 			if (depth == nextDepth && temp.HasMatch("elif"))
 			{
-				if (temp.HasMatch("elif"))
-				{
-					temp.Read("elif".Length);
-					temp.Skip();
+				temp.Read("elif".Length);
+				temp.Skip();
 
-					// Catch up reader
-					reader.Read(temp.Index - reader.Index);
+				// Catch up reader
+				reader.Read(temp.Index - reader.Index);
 
-					var elif = CompileElif(reader, depth);
-					return new Condition(new If(exp, children, elif));
-				}
-				else if (temp.HasMatch("else"))
-				{
-					temp.Read("else".Length);
-					temp.Skip();
+				var elif = CompileElif(reader, depth);
+				return new Condition(new If(exp, children, elif));
+			}
+			else if (depth == nextDepth && temp.HasMatch("else"))
+			{
+				temp.Read("else".Length);
+				temp.Skip();
 
-					// Catch up reader
-					reader.Read(temp.Index - reader.Index);
+				// Catch up reader
+				reader.Read(temp.Index - reader.Index);
 
-					var @else = CompileElse(reader, depth);
-					return new Condition(new If(exp, children, @else));
-				}
+				var @else = CompileElse(reader, depth);
+				return new Condition(new If(exp, children, @else));
 			}
 
 			return new Condition(new If(exp, children));
@@ -364,39 +384,39 @@ private Elif CompileElif(Reader reader, int depth)
 			reader.Expect(':');
 			var children = CompileChildren(reader, depth);
 
-			var temp = GetTempOnNextLine(reader);
+			var temp = GetTempOnNextNonEmptyLine(reader);
 			var nextDepth = temp.Skip();
+
 			if (depth == nextDepth && temp.HasMatch("elif"))
 			{
-				if (temp.HasMatch("elif"))
-				{
-					temp.Read("elif".Length);
-					temp.Skip();
+				temp.Read("elif".Length);
+				temp.Skip();
 
-					// Catch up reader
-					reader.Read(temp.Index - reader.Index);
+				// Catch up reader
+				reader.Read(temp.Index - reader.Index);
 
-					var elif = CompileElif(reader, depth);
-					return new Elif(exp, children, elif);
-				}
-				else if (temp.HasMatch("else"))
-				{
-					temp.Read("else".Length);
-					temp.Skip();
+				var elif = CompileElif(reader, depth);
+				return new Elif(exp, children, elif);
+			}
+			else if (depth == nextDepth && temp.HasMatch("else"))
+			{
+				temp.Read("else".Length);
+				temp.Skip();
 
-					// Catch up reader
-					reader.Read(temp.Index - reader.Index);
+				// Catch up reader
+				reader.Read(temp.Index - reader.Index);
 
-					var @else = CompileElse(reader, depth);
-					return new Elif(exp, children, @else);
-				}
+				var @else = CompileElse(reader, depth);
+				return new Elif(exp, children, @else);
 			}
 
 			return new Elif(exp, children);
 		}
 
 		private Else CompileElse(Reader reader, int depth)
 		{
+			reader.Skip();
+			reader.Expect(':');
 			var children = CompileChildren(reader, depth);
 			return new Else(children);
 		}
@@ -911,7 +931,8 @@ public List<Token> TokenizeExpression(Reader reader)
 						bool isKeyword = false;
 						foreach (var keyword in new List<string>() {
 							"add", "call", "choice", "choose", "clear", "jump",
-							"label", "pause", "return", "say"})
+							"label", "pause", "return", "say", "if", "elif",
+							"else" })
 						{
 							if (temp.HasMatch(keyword))
 							{