From 9acba7431ffaf53ee303a7a7334ba0d7b4ef5087 Mon Sep 17 00:00:00 2001
From: Tangent Wantwight <tangent128@gmail.com>
Date: Mon, 20 May 2024 20:53:06 -0400
Subject: [PATCH] More expr test cases

---
 src/lib/expr.test.ts | 47 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 39 insertions(+), 8 deletions(-)

diff --git a/src/lib/expr.test.ts b/src/lib/expr.test.ts
index fbb0edb..9095d40 100644
--- a/src/lib/expr.test.ts
+++ b/src/lib/expr.test.ts
@@ -2,7 +2,7 @@ import { AsText, TextPiece } from "../words";
 import { Expr } from "./expr";
 
 describe("expr", () => {
-  describe("Expr does math", () => {
+  describe("does math", () => {
     test.each([
       ["1", "1"],
       ["-1", "-1"],
@@ -28,8 +28,6 @@ describe("expr", () => {
       ["6 % -5", "-4"],
       ["-6 % -5", "-1"],
       ["-1 % -5", "-1"],
-      // TODO: operator precedence
-      // TODO: parentheses
     ])("%s", (expression, result) => {
       const actualResult = Expr({}, [{ text: expression }]);
       expect("error" in actualResult).toBeFalsy();
@@ -37,13 +35,46 @@ describe("expr", () => {
     });
   });
 
-  // TODO; error reporting
-  describe("Expr rejects invalid expressions", () => {
-    test.each([["1 $ 2"], ["1 1 + 2"], ["$ 1"]])("%s", (expression) => {
+  describe("handles operator precedence", () => {
+    test.each([
+      ["1 - 2 + 1", "0"],
+      ["1 + 2 * 3", "7"],
+      ["1 / 2 + 3", "3.5"],
+    ])("%s", (expression, result) => {
       const actualResult = Expr({}, [{ text: expression }]);
-      expect("error" in actualResult).toBeTruthy();
+      expect("error" in actualResult).toBeFalsy();
+      expect(AsText(actualResult as TextPiece)).toEqual(result);
     });
   });
 
-  // TODO: handle expr prefix
+  // TODO: parentheses
+
+  // TODO; error reporting
+  describe("rejects invalid expressions", () => {
+    test.each([[""], ["1 $ 2"], ["1 1 + 2"], ["1 + + 2"], ["$ 1"]])(
+      "%s",
+      (expression) => {
+        const actualResult = Expr({}, [{ text: expression }]);
+        expect("error" in actualResult).toBeTruthy();
+      }
+    );
+  });
+
+  // TODO: operators should only be accepted as bare words
+
+  describe("ignores an expr prefix", () => {
+    test.each([
+      [["1", "+", "2"]],
+      [["expr", "1", "+", "2"]],
+      [["1 + 2"]],
+      [["expr", "1 + 2"]],
+    ])("%s", (argv) => {
+      const actualResult = Expr(
+        {},
+        argv.map((text) => ({ bare: text }))
+      );
+      expect("error" in actualResult).toBeFalsy();
+      expect(AsText(actualResult as TextPiece)).toEqual("3");
+    });
+  });
 });