diff --git a/CLAUDE.md b/CLAUDE.md
index 0c51bf5..e2b024e 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -149,11 +149,15 @@ Things worth knowing before editing:
bodies are Markdown, rendered by `src/render/markdown.ts` — escape first, then put
back the constructs we chose to support, never `body_html`. An image in a comment is
written as a token rather than an address — ``,
- ``, `` — and in every case the token is
- a key in that same comment's own `media_metadata`, so `resolveInlineImages` is one
- lookup rather than three special cases. A bare `preview.redd.it` address pasted into a
- comment is in there too, keyed by the id inside the URL. Prefer `s.gif` over `s.mp4`
- for an animated one: a GIF moves in an `![]()
` and an MP4 needs a player. An address
+ ``, `` — and the token is usually a key
+ in that same comment's own `media_metadata`, so `resolveInlineImages` is one lookup
+ rather than three special cases. Usually: plenty of comments carry a Giphy token and
+ no `media_metadata` at all, and Giphy is the one of the three whose id means something
+ off Reddit, so that token alone falls back to `i.giphy.com/media//giphy.gif`. A
+ variant name after the id is dropped — Giphy does not serve every variant of every
+ gif. A bare `preview.redd.it` address pasted into a comment is in there too, keyed by
+ the id inside the URL. Prefer `s.gif` over `s.mp4` for an animated one: a GIF moves in
+ an `![]()
` and an MP4 needs a player. An address
typed without a scheme counts as well, but only when it ends in an image extension —
the rule wants a host, a path *and* that extension, because comments are full of
dotted, slashed prose that must not turn into links.
diff --git a/src/platforms/reddit.ts b/src/platforms/reddit.ts
index fc307b1..2942597 100644
--- a/src/platforms/reddit.ts
+++ b/src/platforms/reddit.ts
@@ -192,14 +192,30 @@ function bodyOf(link: Link): string | undefined {
/** The whole of ``, with the target captured. */
const INLINE_IMAGE = /!\[([^\]\n]*)\]\(([^)\s]+)\)/g;
+/**
+ * A Giphy token, which unlike the others says what it points at.
+ *
+ * Reddit writes a variant name after the id on some of them
+ * (`giphy|abc123|downsized`); only the id is kept, because Giphy does not
+ * serve every variant for every gif but always serves the full one.
+ */
+const GIPHY_TOKEN = /^giphy\|([A-Za-z0-9]+)(?:\|[a-z_]+)?$/;
+
/**
* Point a comment's inline images at something fetchable.
*
* Reddit writes them as ``, ``
- * or `` — a token rather than an address. In every case
- * the token is a key in that same comment's `media_metadata`, which is where
- * the real URL is, so one lookup covers all three and none of them needs
- * naming here.
+ * or `` — a token rather than an address. Usually the
+ * token is a key in that same comment's `media_metadata`, which is where the
+ * real URL is, so one lookup covers all three and none of them needs naming
+ * here.
+ *
+ * Usually, not always: Reddit ships plenty of comments carrying a Giphy token
+ * and no `media_metadata` at all, and with nothing to look the token up in
+ * those showed the token itself where the gif should have been. Giphy is the
+ * one kind that can be resolved without the lookup, the id in it being Giphy's
+ * own, so it falls back to Giphy's address for that id. The other two cannot:
+ * their ids mean nothing off Reddit.
*
* A target that is already an address is not a key, so it falls through
* untouched.
@@ -208,15 +224,17 @@ export function resolveInlineImages(
body: string,
meta: Record | undefined,
): string {
- if (!meta) return body;
-
return body.replace(INLINE_IMAGE, (whole, alt: string, token: string) => {
- const entry = meta[token];
- if (!entry || entry.status !== 'valid') return whole;
- // An animated one has both; the GIF plays in an `![]()
` on its own, which
- // an MP4 does not.
- const url = entry.s?.gif ?? entry.s?.u;
- return url ? `` : whole;
+ const entry = meta?.[token];
+ if (entry?.status === 'valid') {
+ // An animated one has both; the GIF plays in an `![]()
` on its own,
+ // which an MP4 does not.
+ const url = entry.s?.gif ?? entry.s?.u;
+ if (url) return ``;
+ }
+
+ const giphy = GIPHY_TOKEN.exec(token)?.[1];
+ return giphy ? `` : whole;
});
}
diff --git a/test/reddit.test.ts b/test/reddit.test.ts
index 9032a7f..fc96efd 100644
--- a/test/reddit.test.ts
+++ b/test/reddit.test.ts
@@ -224,13 +224,63 @@ test('a target that is already an address is left alone', () => {
});
test('a token with no entry, or a broken one, is not invented', () => {
- assert.equal(resolveInlineImages('', GIPHY), '');
+ // An upload id and an emote id mean nothing off Reddit, so with no entry to
+ // look them up in there is nothing to point them at.
+ assert.equal(resolveInlineImages('', GIPHY), '');
assert.equal(
resolveInlineImages('', { gone: { status: 'failed', e: 'Image' } }),
'',
);
});
+test('a giphy token resolves even when the comment carried no metadata', () => {
+ // Reddit ships plenty of these with no `media_metadata` at all. The id in
+ // the token is Giphy's own, so it does not need Reddit to be readable.
+ assert.equal(
+ resolveInlineImages('', undefined),
+ '',
+ );
+ assert.equal(
+ resolveInlineImages('', GIPHY),
+ '',
+ );
+});
+
+test('the metadata still wins where there is any, being what Reddit will serve', () => {
+ assert.match(resolveInlineImages('', GIPHY), /redd\.it/);
+});
+
+test('a variant name after the id is dropped, not all of them being served', () => {
+ assert.equal(
+ resolveInlineImages('', undefined),
+ '',
+ );
+});
+
+test('only a giphy token is guessed at, and only a well-formed one', () => {
+ for (const token of ['emote|t5_2th52|4358', 'giphy|', 'giphy|../evil', 'giphy|a|b|c']) {
+ assert.equal(resolveInlineImages(``, undefined), ``);
+ }
+});
+
+test('a real comment carrying a giphy token gets the gif', () => {
+ // Captured from the post itself: the comment has the token and no
+ // `media_metadata`, which is the shape that used to show the token instead.
+ const post = toPost(fixture('reddit/video.json'), URL_);
+ const all: string[] = [];
+ const walk = (list: typeof post.comments) => {
+ for (const comment of list ?? []) {
+ if (comment.text) all.push(comment.text);
+ walk(comment.replies);
+ }
+ };
+ walk(post.comments);
+
+ const gif = all.find((text) => text.includes('giphy'));
+ assert.ok(gif, 'the fixture should still carry a giphy comment');
+ assert.match(gif, /!\[gif\]\(https:\/\/i\.giphy\.com\/media\/QfzMP70zmNQiDf5sGP\/giphy\.gif\)/);
+});
+
test('inline images survive the walk into the comment tree', () => {
const { comments } = commentsFrom({
data: {