Lex and parse addition

2 files changed, 32 insertions, 0 deletions

diff --git a/__tests__/parser.test.js b/__tests__/parser.test.js
index 004e18b..b0dc28d 100644
--- a/__tests__/parser.test.js
+++ b/__tests__/parser.test.js
@@ -32,4 +32,28 @@ describe('parse', () => {
       }
     })
   })
+
+  it('parses constant addition', () => {
+    expect(parse('1 + 2')).toEqual({
+      type: 'add',
+      left: { type: 'constant', value: 1 },
+      right: { type: 'constant', value: 2 }
+    })
+  })
+
+  it('parses dice addition', () => {
+    expect(parse('1d6 + 2d8')).toEqual({
+      type: 'add',
+      left: {
+        type: 'd',
+        left: { type: 'constant', value: 1 },
+        right: { type: 'constant', value: 6 }
+      },
+      right: {
+        type: 'd',
+        left: { type: 'constant', value: 2 },
+        right: { type: 'constant', value: 8 }
+      }
+    })
+  })
 })
diff --git a/src/parser.js b/src/parser.js
index 01b5494..c7d91c3 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -24,6 +24,14 @@ newSymbol('d', null, 30, (left, parser) => {
   }
 })
 
+newSymbol('+', null, 20, (left, parser) => {
+  return {
+    type: 'add',
+    left: left,
+    right: parser.expression(20)
+  }
+})
+
 newSymbol('end', null, -1)
 
 const newParser = (tokens) => {