allow sizing commands inside optional groups (#885)

* allow sizing commands inside optional groups

* allow color, old font, and style commands inside optional groups

test/__snapshots__/katex-spec.js.snap

@@ -0,0 +1,178 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`An implicit group parser within optional groups should work style commands \\sqrt[\\textstyle 3]{x} 1`] = `
+[
+  {
+    "type": "sqrt",
+    "mode": "math",
+    "value": {
+      "type": "sqrt",
+      "body": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "mathord",
+            "mode": "math",
+            "value": "x"
+          }
+        ]
+      },
+      "index": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "styling",
+            "mode": "math",
+            "value": {
+              "style": "text",
+              "value": [
+                {
+                  "type": "textord",
+                  "mode": "math",
+                  "value": "3"
+                }
+              ]
+            }
+          }
+        ]
+      }
+    }
+  }
+]
+`;
+
+exports[`An implicit group parser within optional groups should work with \\color: \\sqrt[\\color{red} 3]{x} 1`] = `
+[
+  {
+    "type": "sqrt",
+    "mode": "math",
+    "value": {
+      "type": "sqrt",
+      "body": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "mathord",
+            "mode": "math",
+            "value": "x"
+          }
+        ]
+      },
+      "index": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "color",
+            "mode": "math",
+            "value": {
+              "type": "color",
+              "color": "red",
+              "value": [
+                {
+                  "type": "textord",
+                  "mode": "math",
+                  "value": "3"
+                }
+              ]
+            }
+          }
+        ]
+      }
+    }
+  }
+]
+`;
+
+exports[`An implicit group parser within optional groups should work with sizing commands: \\sqrt[\\small 3]{x} 1`] = `
+[
+  {
+    "type": "sqrt",
+    "mode": "math",
+    "value": {
+      "type": "sqrt",
+      "body": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "mathord",
+            "mode": "math",
+            "value": "x"
+          }
+        ]
+      },
+      "index": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "sizing",
+            "mode": "math",
+            "value": {
+              "size": 5,
+              "value": [
+                {
+                  "type": "textord",
+                  "mode": "math",
+                  "value": "3"
+                }
+              ]
+            }
+          }
+        ]
+      }
+    }
+  }
+]
+`;
+
+exports[`An implicit group parser within optional groups should work wwith old font functions: \\sqrt[\\tt 3]{x} 1`] = `
+[
+  {
+    "type": "sqrt",
+    "mode": "math",
+    "value": {
+      "type": "sqrt",
+      "body": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "mathord",
+            "mode": "math",
+            "value": "x"
+          }
+        ]
+      },
+      "index": {
+        "type": "ordgroup",
+        "mode": "math",
+        "value": [
+          {
+            "type": "font",
+            "mode": "math",
+            "value": {
+              "body": {
+                "type": "ordgroup",
+                "mode": "math",
+                "value": [
+                  {
+                    "type": "textord",
+                    "mode": "math",
+                    "value": "3"
+                  }
+                ]
+              },
+              "font": "mathtt"
+            }
+          }
+        ]
+      }
+    }
+  }
+]
+`;

test/katex-spec.js

@@ -3,6 +3,7 @@
 /* global expect: false */
 /* global it: false */
 /* global describe: false */
+import stringify from 'json-stable-stringify';
 
 import buildMathML from "../src/buildMathML";
 import buildTree from "../src/buildTree";
@@ -13,6 +14,27 @@ import Options from "../src/Options";
 import Settings from "../src/Settings";
 import Style from "../src/Style";
 
+const typeFirstCompare = (a, b) => {
+    if (a.key === 'type') {
+        return -1;
+    } else if (b.key === 'type') {
+        return 1;
+    } else {
+        return a.key < b.key ? -1 : 1;
+    }
+};
+
+const serializer = {
+    print(val) {
+        return stringify(val, {cmp: typeFirstCompare, space: '  '});
+    },
+    test() {
+        return true;
+    },
+};
+
+expect.addSnapshotSerializer(serializer);
+
 const defaultSettings = new Settings({});
 const defaultOptions = new Options({
     style: Style.TEXT,
@@ -520,6 +542,28 @@ describe("An implicit group parser", function() {
         expect(sizing.type).toEqual("sizing");
         expect(sizing.value.value.length).toBe(1);
     });
+
+    describe("within optional groups", () => {
+        it("should work with sizing commands: \\sqrt[\\small 3]{x}", () => {
+            const tree = stripPositions(getParsed("\\sqrt[\\small 3]{x}"));
+            expect(tree).toMatchSnapshot();
+        });
+
+        it("should work with \\color: \\sqrt[\\color{red} 3]{x}", () => {
+            const tree = stripPositions(getParsed("\\sqrt[\\color{red} 3]{x}"));
+            expect(tree).toMatchSnapshot();
+        });
+
+        it("should work style commands \\sqrt[\\textstyle 3]{x}", () => {
+            const tree = stripPositions(getParsed("\\sqrt[\\textstyle 3]{x}"));
+            expect(tree).toMatchSnapshot();
+        });
+
+        it("should work wwith old font functions: \\sqrt[\\tt 3]{x}", () => {
+            const tree = stripPositions(getParsed("\\sqrt[\\tt 3]{x}"));
+            expect(tree).toMatchSnapshot();
+        });
+    });
 });
 
 describe("A function parser", function() {

test/screenshotter/ss_data.yaml

@@ -214,7 +214,7 @@ SizingBaseline:
     pre: x
     post: M
 Sizing: |
-    {\Huge x}{\LARGE y}{\normalsize z}{\scriptsize w}
+    {\Huge x}{\LARGE y}{\normalsize z}{\scriptsize w}\sqrt[\small 3]{x+1}
 Smash: \left( X^{\smash 2} \right) \sqrt{\smash[b]{y}}
 Spacing: ^3+[-1][1-1]1=1(=1)\lvert a\rvert~b
 Sqrt: |