Quick proof-of-concept on formatting

quantified-uncertainty · Apr 18, 2024 · 67006f0 · 67006f0
1 parent fb7c2c1
commit 67006f0
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Showing 3 changed files with 45 additions and 11 deletions.
diff --git a/packages/components/src/components/CodeEditor/useFormatSquiggleExtension.ts b/packages/components/src/components/CodeEditor/useFormatSquiggleExtension.ts
@@ -3,25 +3,37 @@ import * as prettier from "prettier/standalone";
 import { useMemo } from "react";
 
 import * as prettierSquigglePlugin from "@quri/prettier-plugin-squiggle/standalone";
+import { astNodeIsEqual, parse } from "@quri/squiggle-lang";
 
 export async function formatSquiggle(view: EditorView | undefined) {
   if (!view) return;
   const code = view.state.doc.toString();
+  const before = parse(code);
   const { formatted, cursorOffset } = await prettier.formatWithCursor(code, {
     parser: "squiggle",
     plugins: [prettierSquigglePlugin],
     cursorOffset: view.state.selection.main.to,
   });
-  view.dispatch({
-    changes: {
-      from: 0,
-      to: view.state.doc.length,
-      insert: formatted,
-    },
-    selection: {
-      anchor: cursorOffset,
-    },
-  });
+  const after = parse(formatted);
+  if (before.ok !== after.ok) {
+    console.error("ERROR!");
+  } else if (before.ok && after.ok) {
+    const isEqual = astNodeIsEqual(before.value, after.value, true);
+    if (!isEqual) {
+      console.error("ERROR!");
+    } else {
+      view.dispatch({
+        changes: {
+          from: 0,
+          to: view.state.doc.length,
+          insert: formatted,
+        },
+        selection: {
+          anchor: cursorOffset,
+        },
+      });
+    }
+  }
 }
 
 export function useFormatSquiggleExtension() {

diff --git a/packages/squiggle-lang/src/ast/parse.ts b/packages/squiggle-lang/src/ast/parse.ts
@@ -134,3 +134,25 @@ export function nodeResultToString(
   }
   return nodeToString(r.value, printOptions);
 }
+
+export function astNodeIsEqual(
+  node1: ASTNode,
+  node2: ASTNode,
+  compareLocation = false
+): boolean {
+  if (compareLocation) {
+    return (
+      nodeToString(node1) === nodeToString(node2) &&
+      isLocationEqual(node1.location, node2.location)
+    );
+  } else {
+    return nodeToString(node1) === nodeToString(node2);
+  }
+}
+
+function isLocationEqual(loc1: LocationRange, loc2: LocationRange): boolean {
+  return (
+    loc1.start.offset === loc2.start.offset &&
+    loc1.end.offset === loc2.end.offset
+  );
+}
diff --git a/packages/squiggle-lang/src/index.ts b/packages/squiggle-lang/src/index.ts
@@ -86,7 +86,7 @@ export {
   type SqValue,
 };
 
-export { type AST, type ASTNode } from "./ast/parse.js";
+export { type AST, type ASTNode, astNodeIsEqual } from "./ast/parse.js";
 export { type ASTCommentNode } from "./ast/peggyHelpers.js";
 export { type SqLinker } from "./public/SqLinker.js";
 export { type SqOutput, type SqOutputResult } from "./public/types.js";