Parse if expressions

1 files changed, 102 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/parser/ParserIfTests.java b/src/test/java/org/shedlang/compiler/parser/ParserIfTests.java
new file mode 100644
index 00000000..5de0988d
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/parser/ParserIfTests.java
@@ -0,0 +1,102 @@
+package org.shedlang.compiler.parser;
+
+import org.junit.jupiter.api.Test;
+
+import static org.shedlang.compiler.ast.untyped.UntypedNodeMatchers.*;
+import static org.shedlang.compiler.parser.ParserTesting.parseString;
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.isSequence;
+
+public class ParserIfTests {
+    @Test
+    public void canParseIfWithSingleConditionalBranchAndNoElse() {
+        var source = "if (a) { 1; }";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIfNode(
+            isSequence(
+                isUntypedConditionalBranchNode(
+                    isUntypedReferenceNode("a"),
+                    isSequence(
+                        isUntypedExpressionStatementNode(isUntypedIntLiteralNode(1))
+                    )
+                )
+            ),
+            isSequence()
+        ));
+    }
+
+    @Test
+    public void canParseIfWithSingleConditionalBranchAndElse() {
+        var source = "if (a) { 1; } else { 2; }";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIfNode(
+            isSequence(
+                isUntypedConditionalBranchNode(
+                    isUntypedReferenceNode("a"),
+                    isSequence(
+                        isUntypedExpressionStatementNode(isUntypedIntLiteralNode(1))
+                    )
+                )
+            ),
+            isSequence(
+                isUntypedExpressionStatementNode(isUntypedIntLiteralNode(2))
+            )
+        ));
+    }
+
+    @Test
+    public void canParseIfWithManyConditionalBranchesAndNoElse() {
+        var source = "if (a) { 1; } else if (b) { 2; }";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIfNode(
+            isSequence(
+                isUntypedConditionalBranchNode(
+                    isUntypedReferenceNode("a"),
+                    isSequence(
+                        isUntypedExpressionStatementNode(isUntypedIntLiteralNode(1))
+                    )
+                ),
+                isUntypedConditionalBranchNode(
+                    isUntypedReferenceNode("b"),
+                    isSequence(
+                        isUntypedExpressionStatementNode(isUntypedIntLiteralNode(2))
+                    )
+                )
+            ),
+            isSequence()
+        ));
+    }
+
+    @Test
+    public void canParseIfWithManyConditionalBranchesAndElse() {
+        var source = "if (a) { 1; } else if (b) { 2; } else { 3; }";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIfNode(
+            isSequence(
+                isUntypedConditionalBranchNode(
+                    isUntypedReferenceNode("a"),
+                    isSequence(
+                        isUntypedExpressionStatementNode(isUntypedIntLiteralNode(1))
+                    )
+                ),
+                isUntypedConditionalBranchNode(
+                    isUntypedReferenceNode("b"),
+                    isSequence(
+                        isUntypedExpressionStatementNode(isUntypedIntLiteralNode(2))
+                    )
+                )
+            ),
+            isSequence(
+                isUntypedExpressionStatementNode(isUntypedIntLiteralNode(3))
+            )
+        ));
+    }
+}