populate_db: Add images in test data.

This isn't quite the right model, because we're not actually going
through the upload code path, but it does at least provide some inline
image previews in the data.

Fixes part of #14991.

zerver/lib/generate_test_data.py

@@ -54,6 +54,7 @@ def load_generators(config: Dict[str, Any]) -> Dict[str, Any]:
     results["inline-code"] = itertools.cycle(cfg["inline-code"])
     results["code-blocks"] = itertools.cycle(cfg["code-blocks"])
     results["quote-blocks"] = itertools.cycle(cfg["quote-blocks"])
+    results["images"] = itertools.cycle(cfg["images"])
 
     results["lists"] = itertools.cycle(cfg["lists"])
 
@@ -120,8 +121,14 @@ def add_flair(paragraphs: List[str], gens: Dict[str, Any]) -> List[str]:
             txt = add_emoji(paragraphs[i], next(gens["emojis"]))
         elif key == "link":
             txt = add_link(paragraphs[i], next(gens["links"]))
-        elif key == "picture":
+        elif key == "images":
-            txt = txt      # TODO: implement pictures
+            # Ideally, this would actually be a 2-step process that
+            # first hits the `upload` endpoint and then adds that URL;
+            # this is the hacky version where we just use inline image
+            # previews of files already in the project (which are the
+            # only files we can link to as being definitely available
+            # even when developing offline).
+            txt = paragraphs[i] + "\n" + next(gens["images"])
 
         results.append(txt)
 

zerver/tests/fixtures/config.generate_data.json

@@ -44,6 +44,16 @@
         "```quote\nAny sufficiently advanced technology is indistinguishable from magic.\n -- Arthur C. Clarke\n```"
       ],
 
+      "images": [
+            "[whale](/static/images/features/whale.png)\n",
+            "[twitter](/static/images/features/twitter.png)\n",
+            "[topics](/static/images/story-tutorial/zulip-topic.png)\n",
+            "[On_it!](/static/images/story-tutorial/zulip-compose.png)\n",
+            "[streams](/static/images/story-tutorial/zulip-streams.png)\n",
+            "[stream_selected](/static/images/story-tutorial/zulip-streams-selected-original.png)\n",
+            "[unreads](/static/images/story-tutorial/zulip-streams-unreads.png)\n"
+      ],
+
       "maths": [
         "$$e^{i \\pi } + 1 = 0$$",
         "$$\\frac{1}{\\Gamma(k)\\theta^k x^{k-1} e^{-\\frac{x}{\\theta}}$$"
@@ -67,7 +77,7 @@
     "math": 1,
     "link" : 8,
     "list": 5,
-    "picture" : 0
+    "images" : 5
   },
   "corpus":
   {