fix: bug retrieving diff with custom a base sha (#945)

Co-authored-by: repo-ranger[bot] <39074581+repo-ranger[bot]@users.noreply.github.com>

.all-contributorsrc

@@ -169,6 +169,15 @@
         "code",
         "doc"
       ]
+    },
+    {
+      "login": "cfernhout",
+      "name": "Chiel Fernhout",
+      "avatar_url": "https://avatars.githubusercontent.com/u/22294606?v=4",
+      "profile": "https://github.com/cfernhout",
+      "contributions": [
+        "doc"
+      ]
     }
   ],
   "contributorsPerLine": 7,

.github/workflows/test.yml

@@ -950,18 +950,6 @@ jobs:
           fi
         shell:
           bash
-      - name: Run changed-files with custom sha
-        id: changed-files-custom-sha
-        if: github.event_name == 'pull_request' && github.event.action != 'closed'
-        uses: ./
-        with:
-          sha: ${{ github.event.pull_request.head.sha }}
-      - name: Show output
-        if: github.event.action != 'closed'
-        run: |
-          echo '${{ toJSON(steps.changed-files-custom-sha.outputs) }}'
-        shell:
-          bash
       - name: Get branch name
         id: branch-name
         uses: tj-actions/branch-names@v6
@@ -984,6 +972,31 @@ jobs:
           echo '${{ toJSON(steps.changed-files-custom-base-sha.outputs) }}'
         shell:
           bash
+      - name: Run changed-files with custom sha
+        id: changed-files-custom-sha
+        if: github.event_name == 'pull_request' && github.event.action != 'closed'
+        uses: ./
+        with:
+          sha: ${{ github.event.pull_request.head.sha }}
+      - name: Show output
+        if: github.event.action != 'closed'
+        run: |
+          echo '${{ toJSON(steps.changed-files-custom-sha.outputs) }}'
+        shell:
+          bash
+      - name: Run changed-files with the pull request base sha and head sha
+        id: changed-files-pull-request-base-sha-head-sha
+        if: github.event_name == 'pull_request' && github.event.action != 'closed'
+        uses: ./
+        with:
+          base_sha: ${{ github.event.pull_request.base.sha }}
+          sha: ${{ github.event.pull_request.head.sha }}
+      - name: Show output
+        if: github.event.action != 'closed'
+        run: |
+          echo '${{ toJSON(steps.changed-files-pull-request-base-sha-head-sha.outputs) }}'
+        shell:
+          bash
       - name: Run changed-files with specific files (only-changed)
         id: changed-files-specific-only-changed
         uses: ./

.github/workflows/update-readme.yml

@@ -9,14 +9,14 @@ jobs:
   sync-assets:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3.3.0
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0
 
       - name: Run auto-doc
-        uses: tj-actions/auto-doc@v1.7.3
+        uses: tj-actions/auto-doc@v1
 
-      - name: Run test
+      - name: Run remark
         uses: tj-actions/remark@v3
 
       - name: Verify Changed files
@@ -34,7 +34,7 @@ jobs:
 
       - name: Create Pull Request
         if: failure()
-        uses: peter-evans/create-pull-request@v4.2.3
+        uses: peter-evans/create-pull-request@v4
         with:
           base: "main"
           labels: "merge when passing"

HISTORY.md

@@ -1,20 +1,47 @@
 # Changelog
 
-## [Unreleased](https://github.com/tj-actions/changed-files/tree/HEAD)
+## [v35.4.0](https://github.com/tj-actions/changed-files/tree/v35.4.0) (2023-01-05)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35.3.1...HEAD)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35...v35.4.0)
+
+## [v35](https://github.com/tj-actions/changed-files/tree/v35) (2023-01-05)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35.3.2...v35)
+
+**Implemented enhancements:**
+
+- \[Feature\] Skip fetching remote refs for non shallow clones [\#924](https://github.com/tj-actions/changed-files/issues/924)
 
 **Fixed bugs:**
 
 - \[BUG\] v35.3.0 Fails to add \[\] around files when with:json: true [\#926](https://github.com/tj-actions/changed-files/issues/926)
 
+**Merged pull requests:**
+
+- Upgraded to v35.3.2 [\#936](https://github.com/tj-actions/changed-files/pull/936) ([jackton1](https://github.com/jackton1))
+- Updated README.md [\#935](https://github.com/tj-actions/changed-files/pull/935) ([jackton1](https://github.com/jackton1))
+- feat: skip fetching remote refs for non shallow clones [\#934](https://github.com/tj-actions/changed-files/pull/934) ([jackton1](https://github.com/jackton1))
+- fix: error overriding the base sha [\#933](https://github.com/tj-actions/changed-files/pull/933) ([jackton1](https://github.com/jackton1))
+- docs: add cfernhout as a contributor for doc [\#932](https://github.com/tj-actions/changed-files/pull/932) ([allcontributors[bot]](https://github.com/apps/allcontributors))
+- Make example consistent and out of the box usable [\#931](https://github.com/tj-actions/changed-files/pull/931) ([cfernhout](https://github.com/cfernhout))
+
+## [v35.3.2](https://github.com/tj-actions/changed-files/tree/v35.3.2) (2023-01-05)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35.3.1...v35.3.2)
+
+**Closed issues:**
+
+- Dependency Dashboard [\#27](https://github.com/tj-actions/changed-files/issues/27)
+
+**Merged pull requests:**
+
+- fix\(regression\): invalid json output. [\#930](https://github.com/tj-actions/changed-files/pull/930) ([jackton1](https://github.com/jackton1))
+- chore\(deps\): update actions/checkout action to v3.3.0 [\#929](https://github.com/tj-actions/changed-files/pull/929) ([renovate[bot]](https://github.com/apps/renovate))
+- Upgraded to v35.3.1 [\#928](https://github.com/tj-actions/changed-files/pull/928) ([jackton1](https://github.com/jackton1))
+
 ## [v35.3.1](https://github.com/tj-actions/changed-files/tree/v35.3.1) (2023-01-05)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35...v35.3.1)
-
-## [v35](https://github.com/tj-actions/changed-files/tree/v35) (2023-01-05)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35.3.0...v35)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v35.3.0...v35.3.1)
 
 **Fixed bugs:**
 
@@ -29,10 +56,6 @@
 
 [Full Changelog](https://github.com/tj-actions/changed-files/compare/v35.2.1...v35.3.0)
 
-**Closed issues:**
-
-- Dependency Dashboard [\#27](https://github.com/tj-actions/changed-files/issues/27)
-
 **Merged pull requests:**
 
 - fix: bug dirnames output [\#923](https://github.com/tj-actions/changed-files/pull/923) ([jackton1](https://github.com/jackton1))
@@ -576,7 +599,7 @@
 
 ## [v34.0.0](https://github.com/tj-actions/changed-files/tree/v34.0.0) (2022-10-25)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v33.0.0...v34.0.0)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v33...v34.0.0)
 
 **Fixed bugs:**
 
@@ -589,13 +612,13 @@
 - feat: add support for fetching more history [\#709](https://github.com/tj-actions/changed-files/pull/709) ([jackton1](https://github.com/jackton1))
 - Upgraded to v33.0.0 [\#707](https://github.com/tj-actions/changed-files/pull/707) ([jackton1](https://github.com/jackton1))
 
-## [v33.0.0](https://github.com/tj-actions/changed-files/tree/v33.0.0) (2022-10-21)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v33...v33.0.0)
-
 ## [v33](https://github.com/tj-actions/changed-files/tree/v33) (2022-10-21)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v32.1.2...v33)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v33.0.0...v33)
+
+## [v33.0.0](https://github.com/tj-actions/changed-files/tree/v33.0.0) (2022-10-21)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v32...v33.0.0)
 
 **Closed issues:**
 
@@ -614,13 +637,13 @@
 - chore\(deps\): update tj-actions/verify-changed-files action to v12 [\#696](https://github.com/tj-actions/changed-files/pull/696) ([renovate[bot]](https://github.com/apps/renovate))
 - Upgraded to v32.1.2 [\#695](https://github.com/tj-actions/changed-files/pull/695) ([jackton1](https://github.com/jackton1))
 
-## [v32.1.2](https://github.com/tj-actions/changed-files/tree/v32.1.2) (2022-10-16)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v32...v32.1.2)
-
 ## [v32](https://github.com/tj-actions/changed-files/tree/v32) (2022-10-16)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v32.1.1...v32)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v32.1.2...v32)
+
+## [v32.1.2](https://github.com/tj-actions/changed-files/tree/v32.1.2) (2022-10-16)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v32.1.1...v32.1.2)
 
 **Fixed bugs:**
 
@@ -676,7 +699,7 @@
 
 ## [v32.0.0](https://github.com/tj-actions/changed-files/tree/v32.0.0) (2022-10-06)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v31.0.3...v32.0.0)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v31...v32.0.0)
 
 **Merged pull requests:**
 
@@ -687,13 +710,13 @@
 - chore\(deps\): update actions/checkout action to v3.1.0 [\#669](https://github.com/tj-actions/changed-files/pull/669) ([renovate[bot]](https://github.com/apps/renovate))
 - Upgraded to v31.0.3 [\#667](https://github.com/tj-actions/changed-files/pull/667) ([jackton1](https://github.com/jackton1))
 
-## [v31.0.3](https://github.com/tj-actions/changed-files/tree/v31.0.3) (2022-10-02)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v31...v31.0.3)
-
 ## [v31](https://github.com/tj-actions/changed-files/tree/v31) (2022-10-02)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v31.0.2...v31)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v31.0.3...v31)
+
+## [v31.0.3](https://github.com/tj-actions/changed-files/tree/v31.0.3) (2022-10-02)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v31.0.2...v31.0.3)
 
 **Fixed bugs:**
 
@@ -733,7 +756,7 @@
 
 ## [v31.0.0](https://github.com/tj-actions/changed-files/tree/v31.0.0) (2022-09-25)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v30...v31.0.0)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v30.0.0...v31.0.0)
 
 **Merged pull requests:**
 
@@ -746,13 +769,13 @@
 - chore: update broken link [\#642](https://github.com/tj-actions/changed-files/pull/642) ([jackton1](https://github.com/jackton1))
 - Upgraded to v30.0.0 [\#641](https://github.com/tj-actions/changed-files/pull/641) ([jackton1](https://github.com/jackton1))
 
-## [v30](https://github.com/tj-actions/changed-files/tree/v30) (2022-09-24)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v30.0.0...v30)
-
 ## [v30.0.0](https://github.com/tj-actions/changed-files/tree/v30.0.0) (2022-09-24)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v29.0.9...v30.0.0)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v30...v30.0.0)
+
+## [v30](https://github.com/tj-actions/changed-files/tree/v30) (2022-09-24)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v29.0.9...v30)
 
 **Fixed bugs:**
 
@@ -1633,7 +1656,7 @@
 
 ## [v13](https://github.com/tj-actions/changed-files/tree/v13) (2022-02-17)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v12.2...v13)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v2.0.1...v13)
 
 **Implemented enhancements:**
 
@@ -1652,13 +1675,13 @@
 - \[BUG\] wrong result of any\_change output [\#314](https://github.com/tj-actions/changed-files/issues/314)
 - \[BUG\] Investigate possible bug using since\_last\_remote\_commit when force pushing changes. [\#303](https://github.com/tj-actions/changed-files/issues/303)
 
-## [v12.2](https://github.com/tj-actions/changed-files/tree/v12.2) (2021-12-30)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v2.0.1...v12.2)
-
 ## [v2.0.1](https://github.com/tj-actions/changed-files/tree/v2.0.1) (2021-12-30)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v12.1...v2.0.1)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v12.2...v2.0.1)
+
+## [v12.2](https://github.com/tj-actions/changed-files/tree/v12.2) (2021-12-30)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v12.1...v12.2)
 
 **Merged pull requests:**
 
@@ -1812,7 +1835,7 @@
 
 ## [v1.2.1](https://github.com/tj-actions/changed-files/tree/v1.2.1) (2021-11-08)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v1.2.0...v1.2.1)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v11.5...v1.2.1)
 
 **Implemented enhancements:**
 
@@ -1826,13 +1849,13 @@
 - Update actions/checkout action to v2.4.0 [\#243](https://github.com/tj-actions/changed-files/pull/243) ([renovate[bot]](https://github.com/apps/renovate))
 - Upgraded to v11.5 [\#241](https://github.com/tj-actions/changed-files/pull/241) ([jackton1](https://github.com/jackton1))
 
-## [v1.2.0](https://github.com/tj-actions/changed-files/tree/v1.2.0) (2021-10-30)
-
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v11.5...v1.2.0)
-
 ## [v11.5](https://github.com/tj-actions/changed-files/tree/v11.5) (2021-10-30)
 
-[Full Changelog](https://github.com/tj-actions/changed-files/compare/v11.4...v11.5)
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v1.2.0...v11.5)
+
+## [v1.2.0](https://github.com/tj-actions/changed-files/tree/v1.2.0) (2021-10-30)
+
+[Full Changelog](https://github.com/tj-actions/changed-files/compare/v11.4...v1.2.0)
 
 **Merged pull requests:**
 

README.md

@@ -9,7 +9,7 @@
 
 <!-- ALL-CONTRIBUTORS-BADGE:START - Do not remove or modify this section -->
 
-[![All Contributors](https://img.shields.io/badge/all_contributors-18-orange.svg?style=flat-square)](#contributors-)
+[![All Contributors](https://img.shields.io/badge/all_contributors-19-orange.svg?style=flat-square)](#contributors-)
 
 <!-- ALL-CONTRIBUTORS-BADGE:END -->
 
@@ -47,7 +47,7 @@ Retrieve all changed files and directories relative to the target branch or the
 > *   For monorepos where pulling all the branch history might not be desired, you can omit `fetch-depth` for `pull_request` events.
 > *   For files located in a sub-directory ensure that the pattern specified contains `**/` (globstar) to match any preceding directories or explicitly pass the full path relative to the project root. See: [#314](https://github.com/tj-actions/changed-files/issues/314).
 > *   All multiline inputs should not use double or single qoutes since the value is already a string seperated by a newline character. See [Examples](#examples) for more information.
-> *   Ensure that `persist-credentials` is set to `true` when configuring `actions/checkout`.
+> *   Ensure that `persist-credentials` is set to `true` when configuring `actions/checkout` if `fetch-depth` isn't set to `0`.
 
 ```yaml
 name: CI
@@ -64,7 +64,6 @@ on:
     branches:
       - main
 
-
 jobs:
   build:
     runs-on: ubuntu-latest  # windows-latest | macos-latest
@@ -182,7 +181,7 @@ Support this project with a :star:
 |             separator             | string |  false   |        `" "`        |                                                                                                     Split character for output strings                                                                                                      |
 |                sha                | string |  false   |                     |                                                                                        Specify a different commit SHA used<br>for comparing changes                                                                                         |
 |               since               | string |  false   |                     |                                                                             Get changed files for commits whose<br> timestamp is older than the given<br>time.                                                                              |
-|     since\_last\_remote\_commit      | string |   true   |      `"false"`      | Use the last commit on the<br> remote branch as the `base_sha`. Defaults<br> to the last non merge commit<br> on the target branch for pull<br> request events and the previous remote<br> commit of the current branch for<br>push events. |
+|     since\_last\_remote\_commit      | string |  false   |      `"false"`      | Use the last commit on the<br> remote branch as the `base_sha`. Defaults<br> to the last non merge commit<br> on the target branch for pull<br> request events and the previous remote<br> commit of the current branch for<br>push events. |
 |               until               | string |  false   |                     |                                                                            Get changed files for commits whose<br> timestamp is earlier than the given<br>time.                                                                             |
 |        write\_output\_files         | string |  false   |      `"false"`      |                                                                                    Write outputs to files in the<br>`.github/outputs` folder by default.                                                                                    |
 
@@ -285,12 +284,12 @@ See [inputs](#inputs) for more information.
 </details>
 
 <details>
-<summary>Get all changed files using a list of files and take action base on the changes</summary>
+<summary>Get all changed files using a list of files and take action based on the changes</summary>
 
 ```yaml
 ...
     - name: Get changed files
-      id: changed-files
+      id: changed-files-specific
       uses: tj-actions/changed-files@v35
       with:
         files: |
@@ -312,16 +311,16 @@ See [inputs](#inputs) for more information.
         echo "Only files listed above have changed."
 
     - name: Run step if any of the listed files above is deleted
-      if: steps.changed-files.outputs.any_deleted == 'true'
+      if: steps.changed-files-specific.outputs.any_deleted == 'true'
       run: |
-        for file in ${{ steps.changed-files.outputs.deleted_files }}; do
+        for file in ${{ steps.changed-files-specific.outputs.deleted_files }}; do
           echo "$file was deleted"
         done
 
     - name: Run step if all listed files above have been deleted
-      if: steps.changed-files.outputs.only_deleted == 'true'
+      if: steps.changed-files-specific.outputs.only_deleted == 'true'
       run: |
-        for file in ${{ steps.changed-files.outputs.deleted_files }}; do
+        for file in ${{ steps.changed-files-specific.outputs.deleted_files }}; do
           echo "$file was deleted"
         done
 ...
@@ -687,6 +686,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
       <td align="center"><a href="https://github.com/lpulley"><img src="https://avatars.githubusercontent.com/u/7193187?v=4?s=100" width="100px;" alt="Logan Pulley"/><br /><sub><b>Logan Pulley</b></sub></a><br /><a href="https://github.com/tj-actions/changed-files/commits?author=lpulley" title="Code">💻</a></td>
       <td align="center"><a href="https://www.linkedin.com/in/kenji-miyake/"><img src="https://avatars.githubusercontent.com/u/31987104?v=4?s=100" width="100px;" alt="Kenji Miyake"/><br /><sub><b>Kenji Miyake</b></sub></a><br /><a href="https://github.com/tj-actions/changed-files/commits?author=kenji-miyake" title="Code">💻</a></td>
       <td align="center"><a href="https://github.com/adonisgarciac"><img src="https://avatars.githubusercontent.com/u/71078987?v=4?s=100" width="100px;" alt="adonisgarciac"/><br /><sub><b>adonisgarciac</b></sub></a><br /><a href="https://github.com/tj-actions/changed-files/commits?author=adonisgarciac" title="Code">💻</a> <a href="https://github.com/tj-actions/changed-files/commits?author=adonisgarciac" title="Documentation">📖</a></td>
+      <td align="center"><a href="https://github.com/cfernhout"><img src="https://avatars.githubusercontent.com/u/22294606?v=4?s=100" width="100px;" alt="Chiel Fernhout"/><br /><sub><b>Chiel Fernhout</b></sub></a><br /><a href="https://github.com/tj-actions/changed-files/commits?author=cfernhout" title="Documentation">📖</a></td>
     </tr>
   </tbody>
 </table>

action.yml

@@ -89,7 +89,7 @@ inputs:
     default: "50"
   since_last_remote_commit:
     description: "Use the last commit on the remote branch as the `base_sha`. Defaults to the last non merge commit on the target branch for pull request events and the previous remote commit of the current branch for push events."
-    required: true
+    required: false
     default: "false"
   write_output_files:
     description: "Write outputs to files in the `.github/outputs` folder by default."

diff-sha.sh

@@ -54,11 +54,12 @@ if [[ -z $GITHUB_EVENT_PULL_REQUEST_BASE_REF ]]; then
   echo "Running on a push event..."
   TARGET_BRANCH=$GITHUB_REFNAME
   CURRENT_BRANCH=$TARGET_BRANCH
-  
-  echo "Fetching remote refs..."
-  
-  # shellcheck disable=SC2086
-  git fetch $EXTRA_ARGS -u --progress --deepen="$INPUT_FETCH_DEPTH" origin "$CURRENT_BRANCH" 1>/dev/null
+
+  if [[ -f .git/shallow ]]; then
+    echo "Fetching remote refs..."
+    # shellcheck disable=SC2086
+    git fetch $EXTRA_ARGS -u --progress --deepen="$INPUT_FETCH_DEPTH" origin "$CURRENT_BRANCH" 1>/dev/null
+  fi
 
   echo "::debug::Getting HEAD SHA..."
   if [[ -n "$INPUT_UNTIL" ]]; then
@@ -157,9 +158,11 @@ else
     TARGET_BRANCH=$CURRENT_BRANCH
   fi
 
-  echo "Fetching remote refs..."
-  # shellcheck disable=SC2086
-  git fetch $EXTRA_ARGS -u --progress origin pull/"$GITHUB_EVENT_PULL_REQUEST_NUMBER"/head:"$CURRENT_BRANCH" 1>/dev/null
+  if [[ -f .git/shallow ]]; then
+    echo "Fetching remote refs..."
+    # shellcheck disable=SC2086
+    git fetch $EXTRA_ARGS -u --progress origin pull/"$GITHUB_EVENT_PULL_REQUEST_NUMBER"/head:"$CURRENT_BRANCH" 1>/dev/null
+  fi
 
   echo "::debug::Getting HEAD SHA..."
   if [[ -n "$INPUT_UNTIL" ]]; then
@@ -197,9 +200,11 @@ else
         PREVIOUS_SHA=$GITHUB_EVENT_PULL_REQUEST_BASE_SHA
       fi
     else
-      echo "::debug::Fetching remote target branch..."
-      # shellcheck disable=SC2086
-      git fetch -u --progress $EXTRA_ARGS --depth="$INPUT_FETCH_DEPTH" origin +refs/heads/"$TARGET_BRANCH":refs/remotes/origin/"$TARGET_BRANCH" 1>/dev/null
+      if [[ -f .git/shallow ]]; then
+        echo "::debug::Fetching remote target branch..."
+        # shellcheck disable=SC2086
+        git fetch -u --progress $EXTRA_ARGS --depth="$INPUT_FETCH_DEPTH" origin +refs/heads/"$TARGET_BRANCH":refs/remotes/origin/"$TARGET_BRANCH" 1>/dev/null
+      fi
 
       git branch --track "$TARGET_BRANCH" origin/"$TARGET_BRANCH" 1>/dev/null 2>&1 || true
 
@@ -210,18 +215,17 @@ else
       PREVIOUS_SHA=$GITHUB_EVENT_PULL_REQUEST_BASE_SHA && exit_status=$? || exit_status=$?
     fi
 
+    if ! git diff --name-only --ignore-submodules=all "$PREVIOUS_SHA$DIFF$CURRENT_SHA" 1>/dev/null 2>&1; then
+        PREVIOUS_SHA=$(git rev-parse "$TARGET_BRANCH") && exit_status=$? || exit_status=$?
+        DIFF=".."
+    fi
+
     echo "::debug::Previous SHA: $PREVIOUS_SHA"
   else
     PREVIOUS_SHA=$INPUT_BASE_SHA && exit_status=$? || exit_status=$?
-  fi
-
-  if ! git diff --name-only --ignore-submodules=all "$PREVIOUS_SHA$DIFF$CURRENT_SHA" 1>/dev/null 2>&1; then
-    PREVIOUS_SHA=$(git rev-parse "$TARGET_BRANCH") && exit_status=$? || exit_status=$?
-    DIFF=".."
 
     if ! git diff --name-only --ignore-submodules=all "$PREVIOUS_SHA$DIFF$CURRENT_SHA" 1>/dev/null 2>&1; then
-      echo "::error::Unable find a diff between $PREVIOUS_SHA and $CURRENT_SHA"
-      exit 1
+        DIFF=".."
     fi
   fi
 
@@ -236,6 +240,11 @@ else
     echo "::error::Please verify that the previous sha is valid, and increase the fetch_depth to a number higher than $INPUT_FETCH_DEPTH."
     exit 1
   fi
+
+  if ! git diff --name-only --ignore-submodules=all "$PREVIOUS_SHA$DIFF$CURRENT_SHA" 1>/dev/null 2>&1; then
+    echo "::error::Unable to determine a difference between $PREVIOUS_SHA$DIFF$CURRENT_SHA"
+    exit 1
+  fi
 fi
 
 if [[ "$PREVIOUS_SHA" == "$CURRENT_SHA" && "$INITIAL_COMMIT" == "false" ]]; then