checkpoint

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checkpoint.json

@@ -1,19 +1,21 @@
 {
-  "timestamp": "2026-03-16T12:00:34.997886Z",
-  "current_node": "solve",
+  "timestamp": "2026-03-16T12:00:37.460542Z",
+  "current_node": "extract_patch",
   "completed_nodes": [
     "start",
     "setup",
-    "solve"
+    "solve",
+    "extract_patch"
   ],
   "node_retries": {
-    "start": 1,
     "solve": 1,
-    "setup": 1
+    "setup": 1,
+    "start": 1,
+    "extract_patch": 1
   },
   "context_values": {
     "graph.rankdir": "LR",
-    "current_node": "solve",
+    "current_node": "extract_patch",
     "internal.node_visit_count": 1,
     "internal.retry_count.start": 1,
     "graph.goal": "Modeling's `separability_matrix` does not compute separability correctly for nested CompoundModels\nConsider the following model:\r\n\r\n```python\r\nfrom astropy.modeling import models as m\r\nfrom astropy.modeling.separable import separability_matrix\r\n\r\ncm = m.Linear1D(10) & m.Linear1D(5)\r\n```\r\n\r\nIt's separability matrix as you might expect is a diagonal:\r\n\r\n```python\r\n>>> separability_matrix(cm)\r\narray([[ True, False],\r\n       [False,  True]])\r\n```\r\n\r\nIf I make the model more complex:\r\n```python\r\n>>> separability_matrix(m.Pix2Sky_TAN() & m.Linear1D(10) & m.Linear1D(5))\r\narray([[ True,  True, False, False],\r\n       [ True,  True, False, False],\r\n       [False, False,  True, False],\r\n       [False, False, False,  True]])\r\n```\r\n\r\nThe output matrix is again, as expected, the outputs and inputs to the linear models are separable and independent of each other.\r\n\r\nIf however, I nest these compound models:\r\n```python\r\n>>> separability_matrix(m.Pix2Sky_TAN() & cm)\r\narray([[ True,  True, False, False],\r\n       [ True,  True, False, False],\r\n       [False, False,  True,  True],\r\n       [False, False,  True,  True]])\r\n```\r\nSuddenly the inputs and outputs are no longer separable?\r\n\r\nThis feels like a bug to me, but I might be missing something?\n",
@@ -22,17 +24,19 @@
     "response.solve": "The fix is applied. Here's a summary:\n\n## Root Cause\n\nIn `astropy/modeling/separable.py`, the `_cstack` function handles the `&` (concatenation) operator for computing separability matrices. When the right operand is already an ndarray (which happens when it's a nested CompoundModel that has already been recursively evaluated by `_separable`), line 245 was:\n\n```python\ncright[-right.shape[0]:, -right.shape[1]:] = 1\n```\n\nThis set the entire bottom-right block to `1`, **discarding** the actual separability information that was computed for the nested compound model. This made all outputs appear to depend on all inputs for that sub-model.\n\n## Fix\n\nChanged line 245 from `= 1` to `= right`:\n\n```python\ncright[-right.shape[0]:, -right.shape[1]:] = right\n```\n\nThis preserves the actual separability matrix computed for the nested compound model, just like the `left` branch already correctly does on line 240 (`= left`).\n\nThis is a one-line fix that makes the `right` branch consistent with the `left` branch — both now properly copy the pre-computed separability matrix instead of replacing it with all ones.",
     "outcome": "success",
     "last_stage": "solve",
+    "internal.retry_count.extract_patch": 1,
     "thread.start.current_node": "setup",
     "internal.fidelity": "compact",
     "internal.retry_count.solve": 1,
     "thread.setup.current_node": "solve",
-    "internal.thread_id": "setup",
+    "thread.solve.current_node": "extract_patch",
+    "internal.thread_id": "solve",
     "failure_class": "",
     "internal.run_id": "01KKV857H2RFAYPQBG0N9873NR",
-    "current.preamble": "Goal: Modeling's `separability_matrix` does not compute separability correctly for nested CompoundModels\nConsider the following model:\r\n\r\n```python\r\nfrom astropy.modeling import models as m\r\nfrom astropy.modeling.separable import separability_matrix\r\n\r\ncm = m.Linear1D(10) & m.Linear1D(5)\r\n```\r\n\r\nIt's separability matrix as you might expect is a diagonal:\r\n\r\n```python\r\n>>> separability_matrix(cm)\r\narray([[ True, False],\r\n       [False,  True]])\r\n```\r\n\r\nIf I make the model more complex:\r\n```python\r\n>>> separability_matrix(m.Pix2Sky_TAN() & m.Linear1D(10) & m.Linear1D(5))\r\narray([[ True,  True, False, False],\r\n       [ True,  True, False, False],\r\n       [False, False,  True, False],\r\n       [False, False, False,  True]])\r\n```\r\n\r\nThe output matrix is again, as expected, the outputs and inputs to the linear models are separable and independent of each other.\r\n\r\nIf however, I nest these compound models:\r\n```python\r\n>>> separability_matrix(m.Pix2Sky_TAN() & cm)\r\narray([[ True,  True, False, False],\r\n       [ True,  True, False, False],\r\n       [False, False,  True,  True],\r\n       [False, False,  True,  True]])\r\n```\r\nSuddenly the inputs and outputs are no longer separable?\r\n\r\nThis feels like a bug to me, but I might be missing something?\n\n\n## Completed stages\n- **setup**: fail\n  - Script: `git clone https://github.com/astropy/astropy.git . && git checkout d16bfe05a744909de4b27f5875fe0d4ed41ce607 && sed -i 's/requires = \\[\"setuptools\",/requires = \\[\"setuptools==68.0.0\",/' pyproject.toml && python -m pip install -e .[test] --verbose`\n  - Stdout:\n    ```\n    fatal: destination path '.' already exists and is not an empty directory.\n    ```\n  - Stderr: (empty)\n\n## Context\n- failure_class: deterministic\n- failure_signature: setup|deterministic|script failed with exit code: <n> ## stdout fatal: destination path '.' already exists and is not an empty directory.\n",
+    "current.preamble": "Goal: Modeling's `separability_matrix` does not compute separability correctly for nested CompoundModels\nConsider the following model:\r\n\r\n```python\r\nfrom astropy.modeling import models as m\r\nfrom astropy.modeling.separable import separability_matrix\r\n\r\ncm = m.Linear1D(10) & m.Linear1D(5)\r\n```\r\n\r\nIt's separability matrix as you might expect is a diagonal:\r\n\r\n```python\r\n>>> separability_matrix(cm)\r\narray([[ True, False],\r\n       [False,  True]])\r\n```\r\n\r\nIf I make the model more complex:\r\n```python\r\n>>> separability_matrix(m.Pix2Sky_TAN() & m.Linear1D(10) & m.Linear1D(5))\r\narray([[ True,  True, False, False],\r\n       [ True,  True, False, False],\r\n       [False, False,  True, False],\r\n       [False, False, False,  True]])\r\n```\r\n\r\nThe output matrix is again, as expected, the outputs and inputs to the linear models are separable and independent of each other.\r\n\r\nIf however, I nest these compound models:\r\n```python\r\n>>> separability_matrix(m.Pix2Sky_TAN() & cm)\r\narray([[ True,  True, False, False],\r\n       [ True,  True, False, False],\r\n       [False, False,  True,  True],\r\n       [False, False,  True,  True]])\r\n```\r\nSuddenly the inputs and outputs are no longer separable?\r\n\r\nThis feels like a bug to me, but I might be missing something?\n\n\n## Completed stages\n- **setup**: fail\n  - Script: `git clone https://github.com/astropy/astropy.git . && git checkout d16bfe05a744909de4b27f5875fe0d4ed41ce607 && sed -i 's/requires = \\[\"setuptools\",/requires = \\[\"setuptools==68.0.0\",/' pyproject.toml && python -m pip install -e .[test] --verbose`\n  - Stdout:\n    ```\n    fatal: destination path '.' already exists and is not an empty directory.\n    ```\n  - Stderr: (empty)\n- **solve**: success\n  - Model: claude-opus-4-6, 11.4k tokens in / 3.3k out\n  - Files: /home/daytona/workspace/astropy_repo/astropy/modeling/separable.py\n",
     "internal.retry_count.setup": 1,
     "last_response": "The fix is applied. Here's a summary:\n\n## Root Cause\n\nIn `astropy/modeling/separable.py`, the `_cstack` function handles the `&` (concatenation) operator for computing separability matrices. When the ",
-    "command.output": "fatal: destination path '.' already exists and is not an empty directory.\n"
+    "command.output": "diff --git a/astropy_repo b/astropy_repo\n--- a/astropy_repo\n+++ b/astropy_repo\n@@ -1 +1 @@\n-Subproject commit d16bfe05a744909de4b27f5875fe0d4ed41ce607\n+Subproject commit d16bfe05a744909de4b27f5875fe0d4ed41ce607-dirty\n"
   },
   "logs": [],
   "node_outcomes": {
@@ -48,6 +52,15 @@
       },
       "duration_ms": 212
     },
+    "extract_patch": {
+      "status": "success",
+      "context_updates": {
+        "command.stderr": "",
+        "command.output": "diff --git a/astropy_repo b/astropy_repo\n--- a/astropy_repo\n+++ b/astropy_repo\n@@ -1 +1 @@\n-Subproject commit d16bfe05a744909de4b27f5875fe0d4ed41ce607\n+Subproject commit d16bfe05a744909de4b27f5875fe0d4ed41ce607-dirty\n"
+      },
+      "notes": "Script completed: git diff",
+      "duration_ms": 41
+    },
     "start": {
       "status": "success",
       "duration_ms": 0
@@ -75,13 +88,14 @@
       "duration_ms": 144779
     }
   },
-  "next_node_id": "extract_patch",
+  "next_node_id": "exit",
   "loop_failure_signatures": {
     "setup|deterministic|script failed with exit code: <n> ## stdout fatal: destination path '.' already exists and is not an empty directory.": 1
   },
   "node_visits": {
     "start": 1,
     "setup": 1,
-    "solve": 1
+    "solve": 1,
+    "extract_patch": 1
   }
 }

nodes/extract_patch/script_invocation.json

@@ -0,0 +1,5 @@
+{
+  "command": "git diff",
+  "language": "shell",
+  "timeout_ms": null
+}

nodes/extract_patch/script_timing.json

@@ -0,0 +1,5 @@
+{
+  "duration_ms": 40,
+  "exit_code": 0,
+  "timed_out": false
+}

nodes/extract_patch/status.json

@@ -0,0 +1,6 @@
+{
+  "status": "success",
+  "notes": "Script completed: git diff",
+  "failure_reason": null,
+  "timestamp": "2026-03-16T12:00:37.460167+00:00"
+}

nodes/solve/diff.patch

@@ -0,0 +1,7 @@
+diff --git a/astropy_repo b/astropy_repo
+new file mode 160000
+index 0000000..d16bfe0
+--- /dev/null
++++ b/astropy_repo
+@@ -0,0 +1 @@
++Subproject commit d16bfe05a744909de4b27f5875fe0d4ed41ce607