fix: try to fix gist

src/core/Gist.ts

@@ -114,9 +114,6 @@ export default class Gist {
       comments: commentsMapped,
     };
     this._gistPayload = payload;
-    // `gist` is a nested path (not a sub-schema), so assigning the whole
-    // object via set("gist", payload) mis-casts the inner subdoc arrays.
-    // Set each sub-path individually so Mongoose casts arrays correctly.
     this._model.set("gist.description", payload.description);
     this._model.set("gist.isPublic", payload.isPublic);
     this._model.set("gist.creationDate", payload.creationDate);

src/core/model/anonymizedGists/anonymizedGists.schema.ts

@@ -51,7 +51,10 @@ const AnonymizedGistSchema = new Schema({
         content: String,
         language: String,
         size: Number,
-        type: String,
+        // `type` is a reserved key in Mongoose type declarations; without the
+        // nested `{ type: String }` the whole object is compiled as an array
+        // of strings and file objects are silently dropped on save.
+        type: { type: String },
       },
     ],
     comments: [

test/gist-schema.test.js

@@ -0,0 +1,67 @@
+const { expect } = require("chai");
+require("ts-node/register/transpile-only");
+const mongoose = require("mongoose");
+const AnonymizedGistSchema = require("../src/core/model/anonymizedGists/anonymizedGists.schema").default;
+
+/**
+ * Regression test for the empty gist page bug.
+ *
+ * The `files` sub-document declared a data field literally named `type`
+ * (`type: String`). Mongoose treats a bare `type` key as a type
+ * declaration, so `gist.files` was compiled as an array of *strings*
+ * instead of sub-documents. Every downloaded file object then failed
+ * casting and was silently dropped, and gists were saved with
+ * `gist.files: []` — rendering an empty gist page.
+ */
+
+describe("AnonymizedGistSchema gist.files", function () {
+  const Model =
+    mongoose.models.GistSchemaTest ||
+    mongoose.model("GistSchemaTest", AnonymizedGistSchema);
+
+  const files = [
+    {
+      filename: "a.txt",
+      content: "hello world",
+      language: "Text",
+      size: 11,
+      type: "text/plain",
+    },
+    {
+      filename: "b.md",
+      content: "# readme",
+      language: "Markdown",
+      size: 8,
+      type: "text/markdown",
+    },
+  ];
+
+  it("compiles gist.files as a sub-document array, not a string array", function () {
+    const path = AnonymizedGistSchema.path("gist.files");
+    expect(path.constructor.name).to.equal("DocumentArrayPath");
+  });
+
+  it("keeps file objects when set via sub-paths (download() flow)", function () {
+    const doc = new Model({});
+    doc.set("gist.files", files);
+    expect(doc.gist.files).to.have.length(2);
+    expect(doc.gist.files[0].filename).to.equal("a.txt");
+    expect(doc.gist.files[0].content).to.equal("hello world");
+    expect(doc.gist.files[0].type).to.equal("text/plain");
+  });
+
+  it("keeps file objects when passed to the constructor", function () {
+    const doc = new Model({ gist: { files } });
+    expect(doc.gist.files).to.have.length(2);
+    expect(doc.gist.files[1].size).to.equal(8);
+  });
+
+  it("casts gist.files correctly in an updateOne $set (updateIfNeeded flow)", function () {
+    const doc = new Model({});
+    doc.set("gist.files", files);
+    const query = Model.updateOne({ _id: doc._id }, { $set: { gist: doc.gist } });
+    const casted = query._update.$set.gist;
+    expect(casted.files).to.have.length(2);
+    expect(casted.files[0].content).to.equal("hello world");
+  });
+});