From 525a14d83369aa7bf8767fe2b38477bf5895798a Mon Sep 17 00:00:00 2001
From: Augustine Kim <augustinekim@google.com>
Date: Wed, 17 Jan 2024 15:49:54 -0800
Subject: [PATCH 1/4] Add regression test

---
 .../testdata/extract-xliff-merge/goldens/foo.ts               | 2 ++
 .../testdata/extract-xliff-merge/goldens/xliff/es-419.xlf     | 4 ++++
 .../localize-tools/testdata/extract-xliff-merge/input/foo.ts  | 2 ++
 .../testdata/extract-xliff-merge/input/xliff/es-419.xlf       | 4 ++++
 4 files changed, 12 insertions(+)

diff --git a/packages/localize-tools/testdata/extract-xliff-merge/goldens/foo.ts b/packages/localize-tools/testdata/extract-xliff-merge/goldens/foo.ts
index 66fa0d946f..f71b418288 100644
--- a/packages/localize-tools/testdata/extract-xliff-merge/goldens/foo.ts
+++ b/packages/localize-tools/testdata/extract-xliff-merge/goldens/foo.ts
@@ -7,7 +7,9 @@
 import {msg, str} from '@lit/localize';
 
 const who = 'World';
+const kind = 'Small';
 msg(str`I am translated. Hello ${who}.`, {desc: 'Description of translated'});
+msg(str`I am translated with swapped order. Hello ${kind} ish ${who}.`);
 msg('I am not translated', {desc: 'Description of not translated'});
 msg('I am translated with a note', {desc: 'Happy note'});
 msg('My note needs to be migrated', {desc: 'Existing note'});
diff --git a/packages/localize-tools/testdata/extract-xliff-merge/goldens/xliff/es-419.xlf b/packages/localize-tools/testdata/extract-xliff-merge/goldens/xliff/es-419.xlf
index b19084e9ba..f13d163dd4 100644
--- a/packages/localize-tools/testdata/extract-xliff-merge/goldens/xliff/es-419.xlf
+++ b/packages/localize-tools/testdata/extract-xliff-merge/goldens/xliff/es-419.xlf
@@ -8,6 +8,10 @@
       <target state="translated">Estoy traducido. Hola <ph id="0">${who}</ph>.</target>
   <note from="lit-localize">Description of translated</note>
     </trans-unit>
+    <trans-unit id="s648aae3daabd8fcc">
+      <source>I am translated with swapped order. Hello <ph id="0">${kind}</ph> ish <ph id="1">${who}</ph>.</source>
+      <target state="translated">Estoy traducido con orden intercambiada. Hola <ph id="1">${who}</ph> más o menos <ph id="0">${kind}</ph>.</target>
+    </trans-unit>
     <trans-unit id="s18fa8e4d6470399d">
       <source foo:attribute="bar">I am translated with a note</source>
       <target state="translated">Estoy traducido con una nota</target>
diff --git a/packages/localize-tools/testdata/extract-xliff-merge/input/foo.ts b/packages/localize-tools/testdata/extract-xliff-merge/input/foo.ts
index 66fa0d946f..f71b418288 100644
--- a/packages/localize-tools/testdata/extract-xliff-merge/input/foo.ts
+++ b/packages/localize-tools/testdata/extract-xliff-merge/input/foo.ts
@@ -7,7 +7,9 @@
 import {msg, str} from '@lit/localize';
 
 const who = 'World';
+const kind = 'Small';
 msg(str`I am translated. Hello ${who}.`, {desc: 'Description of translated'});
+msg(str`I am translated with swapped order. Hello ${kind} ish ${who}.`);
 msg('I am not translated', {desc: 'Description of not translated'});
 msg('I am translated with a note', {desc: 'Happy note'});
 msg('My note needs to be migrated', {desc: 'Existing note'});
diff --git a/packages/localize-tools/testdata/extract-xliff-merge/input/xliff/es-419.xlf b/packages/localize-tools/testdata/extract-xliff-merge/input/xliff/es-419.xlf
index a74885ab25..f813d86940 100644
--- a/packages/localize-tools/testdata/extract-xliff-merge/input/xliff/es-419.xlf
+++ b/packages/localize-tools/testdata/extract-xliff-merge/input/xliff/es-419.xlf
@@ -7,6 +7,10 @@
       <source>I was translated. Hello <ph id="0">${who}</ph>.</source>
       <target state="translated">Estoy traducido. Hola <ph id="0">${who}</ph>.</target>
     </trans-unit>
+    <trans-unit id="s648aae3daabd8fcc">
+      <source>I am translated with swapped order. Hello <ph id="0">${kind}</ph> ish <ph id="1">${who}</ph>.</source>
+      <target state="translated">Estoy traducido con orden intercambiada. Hola <ph id="1">${who}</ph> más o menos <ph id="0">${kind}</ph>.</target>
+    </trans-unit>
     <trans-unit id="s18fa8e4d6470399d">
       <source foo:attribute="bar">I am translated with a note</source>
       <target state="translated">Estoy traducido con una nota</target>

From f784da8b79acf673d592c60930b67a50e1558cc0 Mon Sep 17 00:00:00 2001
From: Augustine Kim <augustinekim@google.com>
Date: Wed, 17 Jan 2024 16:18:50 -0800
Subject: [PATCH 2/4] Use existing index for placeholder id

---
 packages/localize-tools/src/formatters/xliff.ts | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/packages/localize-tools/src/formatters/xliff.ts b/packages/localize-tools/src/formatters/xliff.ts
index bdc72f6193..58fe01ae6a 100644
--- a/packages/localize-tools/src/formatters/xliff.ts
+++ b/packages/localize-tools/src/formatters/xliff.ts
@@ -278,14 +278,11 @@ export class XliffFormatter implements Formatter {
    */
   private encodeContents(doc: Document, contents: Message['contents']): Node[] {
     const nodes = [];
-    // We need a unique ID within each source for each placeholder. The index
-    // will do.
-    let phIdx = 0;
     for (const content of contents) {
       if (typeof content === 'string') {
         nodes.push(doc.createTextNode(content));
       } else {
-        nodes.push(this.createPlaceholder(doc, String(phIdx++), content));
+        nodes.push(this.createPlaceholder(doc, content));
       }
     }
     return nodes;
@@ -293,10 +290,12 @@ export class XliffFormatter implements Formatter {
 
   private createPlaceholder(
     doc: Document,
-    id: string,
-    {untranslatable}: Placeholder
+    {untranslatable, index}: Placeholder
   ): HTMLElement {
     const style = this.xliffConfig.placeholderStyle ?? 'x';
+    // We need a unique ID within each source for each placeholder. The index
+    // will do.
+    const id = String(index);
     if (style === 'x') {
       // https://docs.oasis-open.org/xliff/v1.2/os/xliff-core.html#x
       const el = doc.createElement('x');

From 21992afdc353f275094bc74193de4943373fc226 Mon Sep 17 00:00:00 2001
From: Augustine Kim <augustinekim@google.com>
Date: Wed, 17 Jan 2024 16:47:30 -0800
Subject: [PATCH 3/4] Add changeset

---
 .changeset/mean-cars-appear.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/mean-cars-appear.md

diff --git a/.changeset/mean-cars-appear.md b/.changeset/mean-cars-appear.md
new file mode 100644
index 0000000000..a4c6f13cb7
--- /dev/null
+++ b/.changeset/mean-cars-appear.md
@@ -0,0 +1,5 @@
+---
+'@lit/localize-tools': patch
+---
+
+Fix an issue where running `extract` on an existing translation target would rewrite the "id" for placeholders signifying the expression index, which breaks translation targets where the expressions need to be reordered.

From 478e6937b2b9c809e82dfd24b3b492166271dea7 Mon Sep 17 00:00:00 2001
From: Augustine Kim <augustinekim@google.com>
Date: Thu, 18 Jan 2024 11:35:07 -0800
Subject: [PATCH 4/4] Apply fix to xlb mode

---
 packages/localize-tools/src/formatters/xlb.ts | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/packages/localize-tools/src/formatters/xlb.ts b/packages/localize-tools/src/formatters/xlb.ts
index 42b22b471b..704e363d75 100644
--- a/packages/localize-tools/src/formatters/xlb.ts
+++ b/packages/localize-tools/src/formatters/xlb.ts
@@ -130,14 +130,13 @@ class XlbFormatter implements Formatter {
       }
       indent(messagesNode, 2);
       messagesNode.appendChild(messageNode);
-      let phIdx = 0;
       for (const content of contents) {
         if (typeof content === 'string') {
           messageNode.appendChild(doc.createTextNode(content));
         } else {
-          const {untranslatable} = content;
+          const {untranslatable, index} = content;
           const ph = doc.createElement('ph');
-          ph.setAttribute('name', String(phIdx++));
+          ph.setAttribute('name', String(index));
           ph.appendChild(doc.createTextNode(untranslatable));
           messageNode.appendChild(ph);
         }