Accept single snippet photos and derive post IDs from titles

photo-upload/tests/test_posts.py

@@ -2,7 +2,7 @@ import io
 import json
 
 from test_upload import AUTH, git, publisher, service
-from posts import content_similarity
+from posts import content_similarity, title_id
 
 
 BODY = "\n\n".join(f"Paragraph {i}: I walked beside the river and considered how memory changes our understanding of a place. The details matter more than the names we give them." for i in range(12))
@@ -32,6 +32,7 @@ def test_content_update_preserves_url_date_and_no_duplicate(publisher, service,
     assert run().returncode == 0
     status = client.get(first.json["status_url"], headers=AUTH).json
     assert status["action"] == "created" and status["url"] == "/my-walk/"
+    assert status["post_id"] == "my-walk"
     second = send(client, "# My revised walk\n\n" + BODY.replace("beside the river", "along the river", 1), "renamed.md")
     result = run()
     assert result.returncode == 0, result.stderr
@@ -79,3 +80,25 @@ def test_similarity_requires_substantial_unambiguous_content():
     assert content_similarity("short shared title", "short shared title") == 0
     assert content_similarity(BODY, BODY.replace("river", "lake", 1)) >= 0.92
     assert content_similarity(BODY, "Completely unrelated writing.") == 0
+
+
+def test_title_derived_id_and_permalink(publisher):
+    run, _, client = publisher
+    response = send(client, "# My New_Post: Hello, World!\n\n" + BODY)
+    assert run().returncode == 0
+    state = client.get(response.json["status_url"], headers=AUTH).json
+    assert state["post_id"] == "my-new-post-hello-world"
+    assert state["url"] == "/my-new-post-hello-world/"
+    assert title_id("  سفر به تهران!  ") == "سفر-به-تهران"
+    assert len(title_id("漢" * 100).encode()) <= 160
+
+
+def test_same_title_does_not_overwrite_unrelated_content(publisher):
+    run, remote, client = publisher
+    send(client, "# Shared title\n\n" + BODY)
+    assert run().returncode == 0
+    head = git(remote, "rev-parse", "master")
+    response = send(client, "# Shared title\n\n" + "An unrelated essay about distant stars. " * 20)
+    assert run().returncode != 0
+    assert client.get(response.json["status_url"], headers=AUTH).json["status"] == "failed"
+    assert git(remote, "rev-parse", "master") == head