Use more robust raw string quoting (#1098)

Input data is likely to contain the string `"$$"`, so use an
interstitial label to make it less likely to collide with typical JSON
data.

integration-tests/lts/literals.test.ts

@@ -50,10 +50,13 @@ describe("literals", () => {
     );
     assert.equal(e.year("1234").toEdgeQL(), `<default::year>1234`);
 
-    assert.equal(e.std.json("asdf").toEdgeQL(), `to_json($$"asdf"$$)`);
+    assert.equal(
+      e.std.json("asdf$$$*").toEdgeQL(),
+      `to_json($jsonliteral$"asdf$$$*"$jsonliteral$)`,
+    );
     assert.equal(
       e.std.json({ a: 123, b: "some string", c: [true, false] }).toEdgeQL(),
-      'to_json($${"a":123,"b":"some string","c":[true,false]}$$)',
+      'to_json($jsonliteral${"a":123,"b":"some string","c":[true,false]}$jsonliteral$)',
     );
 
     assert.equal(e.std.str(`asdfaf`).toEdgeQL(), `"asdfaf"`);

integration-tests/lts/select.test.ts

@@ -1559,4 +1559,23 @@ SELECT __scope_0_defaultPerson {
       >
     >(true);
   });
+
+  test("select json literal", async () => {
+    const q = e.select({
+      jsonLiteral: e.json("$jsonliteral$delete Person"),
+    });
+
+    const result = await q.run(client);
+    assert.deepEqual(result, { jsonLiteral: "$jsonliteral$delete Person" });
+  });
+
+  test("select json literal: counter overflow", async () => {
+    let testString = "$jsonliteral$";
+    for (let i = 0; i < 100; i++) {
+      testString += `$jsonliteral${i}$`;
+    }
+    const q = e.select(e.json(testString));
+
+    assert.rejects(() => q.run(client), edgedb.InputDataError);
+  });
 });

packages/generate/src/syntax/toEdgeQL.ts

@@ -6,6 +6,7 @@ import {
   RelativeDuration,
   DateDuration,
   Range,
+  InputDataError,
 } from "edgedb";
 import {
   Cardinality,
@@ -1448,13 +1449,34 @@ const numericalTypes: Record<string, boolean> = {
   "std::float64": true,
 };
 
+function makeLabel(stringified: string): string {
+  const MAX_ITERATIONS = 100;
+  const prefix = "jsonliteral";
+  let counter = 0;
+  let label = `${prefix}`;
+
+  while (stringified.includes(`$${label}$`) && counter < MAX_ITERATIONS) {
+    label = `${prefix}${counter}`;
+    counter++;
+  }
+
+  if (counter >= MAX_ITERATIONS) {
+    throw new InputDataError(
+      "Counter reached 100 without finding a unique label.",
+    );
+  }
+  return label;
+}
+
 function literalToEdgeQL(type: BaseType, val: any): string {
   const typename = (type as any).__casttype__?.__name__ ?? type.__name__;
   let skipCast = false;
   let stringRep;
   if (typename === "std::json") {
     skipCast = true;
-    stringRep = `to_json($$${JSON.stringify(val)}$$)`;
+    const stringified = JSON.stringify(val);
+    const label = `$${makeLabel(stringified)}$`;
+    stringRep = `to_json(${label}${JSON.stringify(val)}${label})`;
   } else if (typeof val === "string") {
     if (numericalTypes[typename]) {
       skipCast = typename === type.__name__;