1 files changed, 117 insertions, 0 deletions
diff --git a/packages/excalidraw/charts.test.ts b/packages/excalidraw/charts.test.ts
new file mode 100644
index 0000000..fcd8823
--- /dev/null
+++ b/packages/excalidraw/charts.test.ts
@@ -0,0 +1,117 @@
+import type { Spreadsheet } from "./charts";
+import { tryParseCells, tryParseNumber, VALID_SPREADSHEET } from "./charts";
+
+describe("charts", () => {
+  describe("tryParseNumber", () => {
+    it.each<[string, number]>([
+      ["1", 1],
+      ["0", 0],
+      ["-1", -1],
+      ["0.1", 0.1],
+      [".1", 0.1],
+      ["1.", 1],
+      ["424.", 424],
+      ["$1", 1],
+      ["-.1", -0.1],
+      ["-$1", -1],
+      ["$-1", -1],
+    ])("should correctly identify %s as numbers", (given, expected) => {
+      expect(tryParseNumber(given)).toEqual(expected);
+    });
+
+    it.each<[string]>([["a"], ["$"], ["$a"], ["-$a"]])(
+      "should correctly identify %s as not a number",
+      (given) => {
+        expect(tryParseNumber(given)).toBeNull();
+      },
+    );
+  });
+
+  describe("tryParseCells", () => {
+    it("Successfully parses a spreadsheet", () => {
+      const spreadsheet = [
+        ["time", "value"],
+        ["01:00", "61"],
+        ["02:00", "-60"],
+        ["03:00", "85"],
+        ["04:00", "-67"],
+        ["05:00", "54"],
+        ["06:00", "95"],
+      ];
+
+      const result = tryParseCells(spreadsheet);
+
+      expect(result.type).toBe(VALID_SPREADSHEET);
+
+      const { title, labels, values } = (
+        result as { type: typeof VALID_SPREADSHEET; spreadsheet: Spreadsheet }
+      ).spreadsheet;
+
+      expect(title).toEqual("value");
+      expect(labels).toEqual([
+        "01:00",
+        "02:00",
+        "03:00",
+        "04:00",
+        "05:00",
+        "06:00",
+      ]);
+      expect(values).toEqual([61, -60, 85, -67, 54, 95]);
+    });
+
+    it("Uses the second column as the label if it is not a number", () => {
+      const spreadsheet = [
+        ["time", "value"],
+        ["01:00", "61"],
+        ["02:00", "-60"],
+        ["03:00", "85"],
+        ["04:00", "-67"],
+        ["05:00", "54"],
+        ["06:00", "95"],
+      ];
+
+      const result = tryParseCells(spreadsheet);
+
+      expect(result.type).toBe(VALID_SPREADSHEET);
+
+      const { title, labels, values } = (
+        result as { type: typeof VALID_SPREADSHEET; spreadsheet: Spreadsheet }
+      ).spreadsheet;
+
+      expect(title).toEqual("value");
+      expect(labels).toEqual([
+        "01:00",
+        "02:00",
+        "03:00",
+        "04:00",
+        "05:00",
+        "06:00",
+      ]);
+      expect(values).toEqual([61, -60, 85, -67, 54, 95]);
+    });
+
+    it("treats the first column as labels if both columns are numbers", () => {
+      const spreadsheet = [
+        ["time", "value"],
+        ["01", "61"],
+        ["02", "-60"],
+        ["03", "85"],
+        ["04", "-67"],
+        ["05", "54"],
+        ["06", "95"],
+      ];
+
+      const result = tryParseCells(spreadsheet);
+
+      expect(result.type).toBe(VALID_SPREADSHEET);
+
+      const { title, labels, values } = (
+        result as { type: typeof VALID_SPREADSHEET; spreadsheet: Spreadsheet }
+      ).spreadsheet;
+
+      expect(title).toEqual("value");
+      expect(labels).toEqual(["01", "02", "03", "04", "05", "06"]);
+      expect(values).toEqual([61, -60, 85, -67, 54, 95]);
+    });
+  });
+});