Using code blocks for multi-line conditional tests

Author: SteveWilkes

ReadableExpressions.UnitTests/WhenTranslatingConditionals.cs

@@ -97,6 +97,42 @@ public void ShouldTranslateAMultipleLineIfStatement()
             Assert.AreEqual(EXPECTED.TrimStart(), translated);
         }
 
+        [TestMethod]
+        public void ShouldTranslateAMultipleLineIfStatementTest()
+        {
+            var intVariable = Expression.Variable(typeof(int), "i");
+            var one = Expression.Constant(1);
+            var intVariableLessThanOne = Expression.LessThan(intVariable, one);
+            var returnLabel = Expression.Label(typeof(bool), "Return");
+            var returnTrue = Expression.Return(returnLabel, Expression.Constant(true));
+            var ifLessThanOneReturnTrue = Expression.IfThen(intVariableLessThanOne, returnTrue);
+            var five = Expression.Constant(5);
+            var intVariableMoreThanFive = Expression.GreaterThan(intVariable, five);
+            var returnMoreThanFive = Expression.Label(returnLabel, intVariableMoreThanFive);
+            var testBlock = Expression.Block(ifLessThanOneReturnTrue, returnMoreThanFive);
+
+            Expression<Action> writeHello = () => Console.WriteLine("Hello");
+            var writeVariable = Expression.Variable(writeHello.Type, "write");
+            var assignWrite = Expression.Assign(writeVariable, writeHello);
+            var ifTestPassesThenWrite = Expression.IfThen(testBlock, assignWrite);
+
+            var translated = ifTestPassesThenWrite.ToReadableString();
+
+            const string EXPECTED = @"
+if ({
+        if (i < 1)
+        {
+            return true;
+        }
+
+        return i > 5;
+    })
+{
+    write = () => Console.WriteLine(""Hello"");
+}";
+            Assert.AreEqual(EXPECTED.TrimStart(), translated);
+        }
+
         [TestMethod]
         public void ShouldTranslateAnIfElseStatement()
         {

ReadableExpressions/StringExtensions.cs

@@ -106,6 +106,7 @@ private static bool KeepSurroundingParentheses(Expression expression)
             switch (expression.NodeType)
             {
                 case ExpressionType.Conditional:
+                case ExpressionType.Lambda:
                     return true;
 
                 case ExpressionType.Call:
@@ -117,9 +118,6 @@ private static bool KeepSurroundingParentheses(Expression expression)
                     }
 
                     return (expression.NodeType == ExpressionType.Convert);
-
-                case ExpressionType.Lambda:
-                    return ((LambdaExpression)expression).Parameters.Count > 1;
             }
 
             return false;

ReadableExpressions/Translators/ConditionalExpressionTranslator.cs

@@ -43,7 +43,12 @@ public override string Translate(Expression expression, TranslationContext conte
 
         private static string GetTest(ConditionalExpression conditional, TranslationContext context)
         {
-            var test = context.Translate(conditional.Test);
+            var test = context.TranslateAsCodeBlock(conditional.Test);
+
+            if (test.IsMultiLine())
+            {
+                test = test.Indented().TrimStart();
+            }
 
             return test.WithSurroundingParentheses(checkExisting: true);
         }