From d973e9062a94ed862b974eca0ccf666ba626be0d Mon Sep 17 00:00:00 2001
From: Linus Rath <139418639+rathlinus@users.noreply.github.com>
Date: Tue, 3 Nov 2026 00:45:56 +0100
Subject: [PATCH] fix: give a photo's date only from when it was taken, not
 when the file changed

exif.test.ts: the case "falls back to the file date" now expects no
date, since IFD0's DateTime is the file's change date, not the date
the photo was taken.
---
 lib/__tests__/exif.test.ts | 4 ++--
 lib/exif.ts                | 5 ++---
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/lib/__tests__/exif.test.ts b/lib/__tests__/exif.test.ts
index 31e4ddd88..2e18542e2 100644
--- a/lib/__tests__/exif.test.ts
+++ b/lib/__tests__/exif.test.ts
@@ -72,9 +72,9 @@ describe('readPhotoExif', () => {
     }
   });
 
-  it('falls back to the file date when the original date is missing', () => {
+  it('gives no date when only the date the file changed is there', () => {
     const bytes = jpeg(tiff(false, { ifd0: [{ tag: 0x0132, type: 2, ascii: '2026:11:01 09:00:00' }], exif: [], gps: [] }));
-    expect(readPhotoExif(bytes)).toEqual({ taken: '2026-11-01T09:00:00' });
+    expect(readPhotoExif(bytes)).toEqual({});
   });
 
   it('gives nothing for a JPEG without EXIF, a PNG or broken bytes', () => {
diff --git a/lib/exif.ts b/lib/exif.ts
index cde7a8bc4..4c5a0cf7c 100644
--- a/lib/exif.ts
+++ b/lib/exif.ts
@@ -12,7 +12,6 @@ export interface PhotoExif {
 
 const TAG_EXIF_IFD = 0x8769;
 const TAG_GPS_IFD = 0x8825;
-const TAG_DATETIME = 0x0132;
 const TAG_DATETIME_ORIGINAL = 0x9003;
 const TAG_OFFSET_TIME_ORIGINAL = 0x9011;
 const GPS_LAT_REF = 1;
@@ -126,8 +125,8 @@ export function readPhotoExif(data: ArrayBuffer | Uint8Array): PhotoExif {
     const ifd0 = tiff.ifd(tiff.firstIfd());
     const exifAt = tiff.long(ifd0.get(TAG_EXIF_IFD));
     const exif = exifAt ? tiff.ifd(exifAt) : new Map<number, Entry>();
-    const taken = exifDate(tiff.ascii(exif.get(TAG_DATETIME_ORIGINAL)), tiff.ascii(exif.get(TAG_OFFSET_TIME_ORIGINAL)))
-      ?? exifDate(tiff.ascii(ifd0.get(TAG_DATETIME)), undefined);
+    // Only the date the photo was taken: IFD0's DateTime is when the file was last changed.
+    const taken = exifDate(tiff.ascii(exif.get(TAG_DATETIME_ORIGINAL)), tiff.ascii(exif.get(TAG_OFFSET_TIME_ORIGINAL)));
     if (taken) out.taken = taken;
     const gpsAt = tiff.long(ifd0.get(TAG_GPS_IFD));
     if (gpsAt) {