Parse positive ints

2 files changed, 52 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/ast/untyped/UntypedNodeMatchers.java b/src/test/java/org/shedlang/compiler/ast/untyped/UntypedNodeMatchers.java
index a848b601..acddc159 100644
--- a/src/test/java/org/shedlang/compiler/ast/untyped/UntypedNodeMatchers.java
+++ b/src/test/java/org/shedlang/compiler/ast/untyped/UntypedNodeMatchers.java
@@ -2,6 +2,8 @@ package org.shedlang.compiler.ast.untyped;
 
 import org.zwobble.precisely.Matcher;
 
+import java.math.BigInteger;
+
 import static org.zwobble.precisely.Matchers.*;
 
 public class UntypedNodeMatchers {
@@ -29,6 +31,17 @@ public class UntypedNodeMatchers {
         return UntypedFunctionDefinitionNodeMatcher.empty();
     }
 
+    public static Matcher<UntypedExpressionNode> isUntypedIntLiteralNode(int value) {
+        return isUntypedIntLiteralNode(BigInteger.valueOf(value));
+    }
+
+    public static Matcher<UntypedExpressionNode> isUntypedIntLiteralNode(BigInteger value) {
+        return instanceOf(
+            UntypedIntLiteralNode.class,
+            has("value", x -> x.value(), equalTo(value))
+        );
+    }
+
     public static Matcher<UntypedNamedArgNode> isUntypedNamedArgNode(
         String name,
         Matcher<UntypedExpressionNode> expression
diff --git a/src/test/java/org/shedlang/compiler/parser/ParserIntLiteralTests.java b/src/test/java/org/shedlang/compiler/parser/ParserIntLiteralTests.java
new file mode 100644
index 00000000..61908772
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/parser/ParserIntLiteralTests.java
@@ -0,0 +1,39 @@
+package org.shedlang.compiler.parser;
+
+import org.junit.jupiter.api.Test;
+
+import static org.shedlang.compiler.ast.untyped.UntypedNodeMatchers.isUntypedIntLiteralNode;
+import static org.shedlang.compiler.parser.ParserTesting.parseString;
+import static org.zwobble.precisely.AssertThat.assertThat;
+
+public class ParserIntLiteralTests {
+    // TODO: negatives
+    // TODO: forbid leading zeroes?
+
+    @Test
+    public void canParseZero() {
+        var source = "0";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIntLiteralNode(0));
+    }
+
+    @Test
+    public void canParseSingleDigitPositiveInt() {
+        var source = "7";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIntLiteralNode(7));
+    }
+
+    @Test
+    public void canParseManyDigitPositiveInt() {
+        var source = "723";
+
+        var node = parseString(source, Parser::parseTopLevelExpression);
+
+        assertThat(node, isUntypedIntLiteralNode(723));
+    }
+}