Parse string literals

2 files changed, 72 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/ast/UntypedNodeMatchers.java b/src/test/java/org/shedlang/compiler/ast/UntypedNodeMatchers.java
new file mode 100644
index 00000000..6e0c7654
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/ast/UntypedNodeMatchers.java
@@ -0,0 +1,17 @@
+package org.shedlang.compiler.ast;
+
+import org.zwobble.precisely.Matcher;
+
+import static org.zwobble.precisely.Matchers.*;
+
+public class UntypedNodeMatchers {
+    private UntypedNodeMatchers() {
+    }
+
+    public static Matcher<UntypedExpressionNode> isUntypedStringLiteralNode(String value) {
+        return instanceOf(
+            UntypedStringLiteralNode.class,
+            has("value", x -> x.value(), equalTo(value))
+        );
+    }
+}
diff --git a/src/test/java/org/shedlang/compiler/parser/ParserStringLiteralTests.java b/src/test/java/org/shedlang/compiler/parser/ParserStringLiteralTests.java
new file mode 100644
index 00000000..d625a603
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/parser/ParserStringLiteralTests.java
@@ -0,0 +1,55 @@
+package org.shedlang.compiler.parser;
+
+import org.junit.jupiter.api.Test;
+import org.shedlang.compiler.sources.FileFragmentSource;
+
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.shedlang.compiler.ast.UntypedNodeMatchers.isUntypedStringLiteralNode;
+import static org.shedlang.compiler.parser.ParserTesting.parseString;
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.*;
+
+public class ParserStringLiteralTests {
+    @Test
+    public void canParseEmptyString() {
+        var source = "\"\"";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedStringLiteralNode(""));
+    }
+
+    @Test
+    public void canParseStringWithUnescapedCharacters() {
+        var source = "\"abc 123 XYZ\"";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedStringLiteralNode("abc 123 XYZ"));
+    }
+
+    @Test
+    public void canParseStringWithEscapedCharacters() {
+        var source = "\"\\n\\r\\t\\\\\\\"\"";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedStringLiteralNode("\n\r\t\\\""));
+    }
+
+    @Test
+    public void whenStringHasUnrecognisedEscapeSequenceThenExceptionIsThrown() {
+        var source = "\"a\\ab\"";
+
+        var error = assertThrows(
+            UnrecognisedEscapeSequenceError.class,
+            () -> parseString(source, Parser::parseTopLevelExpression)
+        );
+
+        assertThat(error.getMessage(), equalTo("Unrecognised escape sequence: \\a"));
+        assertThat(error.getSource(), instanceOf(FileFragmentSource.class, allOf(
+            has("characterIndexStart", x -> x.characterIndexStart(), equalTo(1)),
+            has("characterIndexEnd", x -> x.characterIndexEnd(), equalTo(3))
+        )));
+    }
+}