From 68a21c5a5952913d6192be747efd245887bc36cc Mon Sep 17 00:00:00 2001
From: Alexis Placet <2400067+Alex-PLACET@users.noreply.github.com>
Date: Thu, 30 Apr 2026 13:24:54 +0200
Subject: [PATCH 1/4] Fix substring calculation in CSV cell parsing and add
 lexical_cast for signed and unsigned char

---
 include/xtensor/io/xcsv.hpp | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/include/xtensor/io/xcsv.hpp b/include/xtensor/io/xcsv.hpp
index 080ccaf54..2fd347745 100644
--- a/include/xtensor/io/xcsv.hpp
+++ b/include/xtensor/io/xcsv.hpp
@@ -66,7 +66,7 @@ namespace xt
             }
 
             size_t last = cell.find_last_not_of(' ');
-            return cell.substr(first, last == std::string::npos ? cell.size() : last + 1);
+            return cell.substr(first, last == std::string::npos ? cell.size() : last - first + 1);
         }
 
         template <>
@@ -93,6 +93,18 @@ namespace xt
             return std::stoi(cell);
         }
 
+        template <>
+        inline signed char lexical_cast<signed char>(const std::string& cell)
+        {
+            return static_cast<signed char>(std::stoi(cell));
+        }
+
+        template <>
+        inline unsigned char lexical_cast<unsigned char>(const std::string& cell)
+        {
+            return static_cast<unsigned char>(std::stoul(cell));
+        }
+
         template <>
         inline long lexical_cast<long>(const std::string& cell)
         {

From 692aad0cb4d94f3cf5944d9ad49f874e232b94ce Mon Sep 17 00:00:00 2001
From: Alexis Placet <alexis.placet.dev@pm.me>
Date: Thu, 27 Aug 2026 15:28:26 +0200
Subject: [PATCH 2/4] Create release action

---
 .github/workflows/release.yaml | 139 +++++++++++++++++++++++++++++++++
 1 file changed, 139 insertions(+)
 create mode 100644 .github/workflows/release.yaml

diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
new file mode 100644
index 000000000..ce4a645f2
--- /dev/null
+++ b/.github/workflows/release.yaml
@@ -0,0 +1,139 @@
+name: Release
+
+on:
+  workflow_dispatch:
+    inputs:
+      version_type:
+        description: 'Type of version bump'
+        required: true
+        default: 'patch'
+        type: choice
+        options:
+          - patch
+          - minor
+          - major
+      custom_version:
+        description: 'Custom version (optional, overrides version_type)'
+        required: false
+        type: string
+      prerelease:
+        description: 'Create a prerelease'
+        required: false
+        default: false
+        type: boolean
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Determine version
+        id: version
+        run: |
+          if [ -n "${{ github.event.inputs.custom_version }}" ]; then
+            BASE_VERSION="${{ github.event.inputs.custom_version }}"
+          else
+            # Get current version from header file
+            if [ ! -f "include/xtensor/core/xtensor_config.hpp" ]; then
+              echo "Error: xtensor_config.hpp not found"
+              exit 1
+            fi
+
+            CURRENT_MAJOR=$(grep "#define XTENSOR_VERSION_MAJOR" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
+            CURRENT_MINOR=$(grep "#define XTENSOR_VERSION_MINOR" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
+            CURRENT_PATCH=$(grep "#define XTENSOR_VERSION_PATCH" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
+
+            # Verify version numbers were found
+            if [ -z "$CURRENT_MAJOR" ] || [ -z "$CURRENT_MINOR" ] || [ -z "$CURRENT_PATCH" ]; then
+              echo "Error: Could not parse current version from header file"
+              exit 1
+            fi
+
+            echo "Current version: ${CURRENT_MAJOR}.${CURRENT_MINOR}.${CURRENT_PATCH}"
+
+            case "${{ github.event.inputs.version_type }}" in
+              "major")
+                BASE_VERSION="$((CURRENT_MAJOR + 1)).0.0"
+                ;;
+              "minor")
+                BASE_VERSION="${CURRENT_MAJOR}.$((CURRENT_MINOR + 1)).0"
+                ;;
+              "patch")
+                BASE_VERSION="${CURRENT_MAJOR}.${CURRENT_MINOR}.$((CURRENT_PATCH + 1))"
+                ;;
+            esac
+          fi
+
+          # Handle prerelease
+          if [ "${{ github.event.inputs.prerelease }}" = "true" ]; then
+            # Find existing prerelease tags for this version
+            EXISTING_TAGS=$(git tag -l "${BASE_VERSION}_r*" | sort -V)
+
+            if [ -z "$EXISTING_TAGS" ]; then
+              # No existing prereleases, start with _r0
+              PRERELEASE_NUM=0
+            else
+              # Get the highest prerelease number and increment
+              LAST_TAG=$(echo "$EXISTING_TAGS" | tail -n 1)
+              PRERELEASE_NUM=$(echo "$LAST_TAG" | sed "s/${BASE_VERSION}_r//" | sed 's/^0*//')
+              if [ -z "$PRERELEASE_NUM" ]; then
+                PRERELEASE_NUM=0
+              fi
+              PRERELEASE_NUM=$((PRERELEASE_NUM + 1))
+            fi
+
+            FINAL_VERSION="${BASE_VERSION}_r${PRERELEASE_NUM}"
+            echo "is_prerelease=true" >> $GITHUB_OUTPUT
+          else
+            FINAL_VERSION="$BASE_VERSION"
+            echo "is_prerelease=false" >> $GITHUB_OUTPUT
+          fi
+
+          echo "Final version: $FINAL_VERSION"
+          echo "version=$FINAL_VERSION" >> $GITHUB_OUTPUT
+          echo "base_version=$BASE_VERSION" >> $GITHUB_OUTPUT
+
+      - name: Update version in header file
+        run: |
+          BASE_VERSION="${{ steps.version.outputs.base_version }}"
+          IFS='.' read -r NEW_MAJOR NEW_MINOR NEW_PATCH <<< "$BASE_VERSION"
+
+          # Only update header file for non-prerelease versions
+          if [ "${{ steps.version.outputs.is_prerelease }}" = "false" ]; then
+            # Update version numbers in header file
+            sed -i "s/^#define XTENSOR_VERSION_MAJOR [0-9]*/#define XTENSOR_VERSION_MAJOR $NEW_MAJOR/" include/xtensor/core/xtensor_config.hpp
+            sed -i "s/^#define XTENSOR_VERSION_MINOR [0-9]*/#define XTENSOR_VERSION_MINOR $NEW_MINOR/" include/xtensor/core/xtensor_config.hpp
+            sed -i "s/^#define XTENSOR_VERSION_PATCH [0-9]*/#define XTENSOR_VERSION_PATCH $NEW_PATCH/" include/xtensor/core/xtensor_config.hpp
+
+            git config --local user.name "GitHub Action"
+            git add include/xtensor/core/xtensor_config.hpp
+            git commit -m "Release version ${{ steps.version.outputs.version }}"
+          else
+            echo "Skipping header file update for prerelease"
+            git config --local user.name "GitHub Action"
+          fi
+
+      - name: Create tag
+        run: |
+          git tag -a "${{ steps.version.outputs.version }}" -m "Release version ${{ steps.version.outputs.version }}"
+
+      - name: Push changes and tag
+        run: |
+          git push origin master
+          git push origin "${{ steps.version.outputs.version }}"
+
+      - name: Create GitHub Release
+        uses: elgohr/Github-Release-Action@v5
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          title: "Release ${{ steps.version.outputs.version }}"
+          tag: "${{ steps.version.outputs.version }}"
+          prerelease: ${{ steps.version.outputs.is_prerelease }}

From 8e1a6a52376f70811159fe73b351289053456ae8 Mon Sep 17 00:00:00 2001
From: Alexis Placet <alexis.placet@quantstack.net>
Date: Thu, 27 Aug 2026 15:33:09 +0200
Subject: [PATCH 3/4] fix yaml

---
 .github/workflows/release.yaml | 214 ++++++++++++++++-----------------
 1 file changed, 107 insertions(+), 107 deletions(-)

diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index ce4a645f2..6bab51cd6 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -4,20 +4,20 @@ on:
   workflow_dispatch:
     inputs:
       version_type:
-        description: 'Type of version bump'
+        description: Type of version bump
         required: true
-        default: 'patch'
+        default: patch
         type: choice
         options:
-          - patch
-          - minor
-          - major
+        - patch
+        - minor
+        - major
       custom_version:
-        description: 'Custom version (optional, overrides version_type)'
+        description: Custom version (optional, overrides version_type)
         required: false
         type: string
       prerelease:
-        description: 'Create a prerelease'
+        description: Create a prerelease
         required: false
         default: false
         type: boolean
@@ -29,111 +29,111 @@ jobs:
       contents: write
 
     steps:
-      - name: Checkout
-        uses: actions/checkout@v6
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Determine version
-        id: version
-        run: |
-          if [ -n "${{ github.event.inputs.custom_version }}" ]; then
-            BASE_VERSION="${{ github.event.inputs.custom_version }}"
-          else
-            # Get current version from header file
-            if [ ! -f "include/xtensor/core/xtensor_config.hpp" ]; then
-              echo "Error: xtensor_config.hpp not found"
-              exit 1
-            fi
-
-            CURRENT_MAJOR=$(grep "#define XTENSOR_VERSION_MAJOR" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
-            CURRENT_MINOR=$(grep "#define XTENSOR_VERSION_MINOR" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
-            CURRENT_PATCH=$(grep "#define XTENSOR_VERSION_PATCH" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
-
-            # Verify version numbers were found
-            if [ -z "$CURRENT_MAJOR" ] || [ -z "$CURRENT_MINOR" ] || [ -z "$CURRENT_PATCH" ]; then
-              echo "Error: Could not parse current version from header file"
-              exit 1
-            fi
-
-            echo "Current version: ${CURRENT_MAJOR}.${CURRENT_MINOR}.${CURRENT_PATCH}"
-
-            case "${{ github.event.inputs.version_type }}" in
-              "major")
-                BASE_VERSION="$((CURRENT_MAJOR + 1)).0.0"
-                ;;
-              "minor")
-                BASE_VERSION="${CURRENT_MAJOR}.$((CURRENT_MINOR + 1)).0"
-                ;;
-              "patch")
-                BASE_VERSION="${CURRENT_MAJOR}.${CURRENT_MINOR}.$((CURRENT_PATCH + 1))"
-                ;;
-            esac
+    - name: Checkout
+      uses: actions/checkout@v6
+      with:
+        token: ${{ secrets.GITHUB_TOKEN }}
+
+    - name: Determine version
+      id: version
+      run: |
+        if [ -n "${{ github.event.inputs.custom_version }}" ]; then
+          BASE_VERSION="${{ github.event.inputs.custom_version }}"
+        else
+          # Get current version from header file
+          if [ ! -f "include/xtensor/core/xtensor_config.hpp" ]; then
+            echo "Error: xtensor_config.hpp not found"
+            exit 1
           fi
 
-          # Handle prerelease
-          if [ "${{ github.event.inputs.prerelease }}" = "true" ]; then
-            # Find existing prerelease tags for this version
-            EXISTING_TAGS=$(git tag -l "${BASE_VERSION}_r*" | sort -V)
+          CURRENT_MAJOR=$(grep "#define XTENSOR_VERSION_MAJOR" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
+          CURRENT_MINOR=$(grep "#define XTENSOR_VERSION_MINOR" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
+          CURRENT_PATCH=$(grep "#define XTENSOR_VERSION_PATCH" include/xtensor/core/xtensor_config.hpp | awk '{print $3}')
 
-            if [ -z "$EXISTING_TAGS" ]; then
-              # No existing prereleases, start with _r0
-              PRERELEASE_NUM=0
-            else
-              # Get the highest prerelease number and increment
-              LAST_TAG=$(echo "$EXISTING_TAGS" | tail -n 1)
-              PRERELEASE_NUM=$(echo "$LAST_TAG" | sed "s/${BASE_VERSION}_r//" | sed 's/^0*//')
-              if [ -z "$PRERELEASE_NUM" ]; then
-                PRERELEASE_NUM=0
-              fi
-              PRERELEASE_NUM=$((PRERELEASE_NUM + 1))
-            fi
-
-            FINAL_VERSION="${BASE_VERSION}_r${PRERELEASE_NUM}"
-            echo "is_prerelease=true" >> $GITHUB_OUTPUT
-          else
-            FINAL_VERSION="$BASE_VERSION"
-            echo "is_prerelease=false" >> $GITHUB_OUTPUT
+          # Verify version numbers were found
+          if [ -z "$CURRENT_MAJOR" ] || [ -z "$CURRENT_MINOR" ] || [ -z "$CURRENT_PATCH" ]; then
+            echo "Error: Could not parse current version from header file"
+            exit 1
           fi
 
-          echo "Final version: $FINAL_VERSION"
-          echo "version=$FINAL_VERSION" >> $GITHUB_OUTPUT
-          echo "base_version=$BASE_VERSION" >> $GITHUB_OUTPUT
-
-      - name: Update version in header file
-        run: |
-          BASE_VERSION="${{ steps.version.outputs.base_version }}"
-          IFS='.' read -r NEW_MAJOR NEW_MINOR NEW_PATCH <<< "$BASE_VERSION"
-
-          # Only update header file for non-prerelease versions
-          if [ "${{ steps.version.outputs.is_prerelease }}" = "false" ]; then
-            # Update version numbers in header file
-            sed -i "s/^#define XTENSOR_VERSION_MAJOR [0-9]*/#define XTENSOR_VERSION_MAJOR $NEW_MAJOR/" include/xtensor/core/xtensor_config.hpp
-            sed -i "s/^#define XTENSOR_VERSION_MINOR [0-9]*/#define XTENSOR_VERSION_MINOR $NEW_MINOR/" include/xtensor/core/xtensor_config.hpp
-            sed -i "s/^#define XTENSOR_VERSION_PATCH [0-9]*/#define XTENSOR_VERSION_PATCH $NEW_PATCH/" include/xtensor/core/xtensor_config.hpp
-
-            git config --local user.name "GitHub Action"
-            git add include/xtensor/core/xtensor_config.hpp
-            git commit -m "Release version ${{ steps.version.outputs.version }}"
+          echo "Current version: ${CURRENT_MAJOR}.${CURRENT_MINOR}.${CURRENT_PATCH}"
+
+          case "${{ github.event.inputs.version_type }}" in
+            "major")
+              BASE_VERSION="$((CURRENT_MAJOR + 1)).0.0"
+              ;;
+            "minor")
+              BASE_VERSION="${CURRENT_MAJOR}.$((CURRENT_MINOR + 1)).0"
+              ;;
+            "patch")
+              BASE_VERSION="${CURRENT_MAJOR}.${CURRENT_MINOR}.$((CURRENT_PATCH + 1))"
+              ;;
+          esac
+        fi
+
+        # Handle prerelease
+        if [ "${{ github.event.inputs.prerelease }}" = "true" ]; then
+          # Find existing prerelease tags for this version
+          EXISTING_TAGS=$(git tag -l "${BASE_VERSION}_r*" | sort -V)
+
+          if [ -z "$EXISTING_TAGS" ]; then
+            # No existing prereleases, start with _r0
+            PRERELEASE_NUM=0
           else
-            echo "Skipping header file update for prerelease"
-            git config --local user.name "GitHub Action"
+            # Get the highest prerelease number and increment
+            LAST_TAG=$(echo "$EXISTING_TAGS" | tail -n 1)
+            PRERELEASE_NUM=$(echo "$LAST_TAG" | sed "s/${BASE_VERSION}_r//" | sed 's/^0*//')
+            if [ -z "$PRERELEASE_NUM" ]; then
+              PRERELEASE_NUM=0
+            fi
+            PRERELEASE_NUM=$((PRERELEASE_NUM + 1))
           fi
 
-      - name: Create tag
-        run: |
-          git tag -a "${{ steps.version.outputs.version }}" -m "Release version ${{ steps.version.outputs.version }}"
-
-      - name: Push changes and tag
-        run: |
-          git push origin master
-          git push origin "${{ steps.version.outputs.version }}"
-
-      - name: Create GitHub Release
-        uses: elgohr/Github-Release-Action@v5
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        with:
-          title: "Release ${{ steps.version.outputs.version }}"
-          tag: "${{ steps.version.outputs.version }}"
-          prerelease: ${{ steps.version.outputs.is_prerelease }}
+          FINAL_VERSION="${BASE_VERSION}_r${PRERELEASE_NUM}"
+          echo "is_prerelease=true" >> $GITHUB_OUTPUT
+        else
+          FINAL_VERSION="$BASE_VERSION"
+          echo "is_prerelease=false" >> $GITHUB_OUTPUT
+        fi
+
+        echo "Final version: $FINAL_VERSION"
+        echo "version=$FINAL_VERSION" >> $GITHUB_OUTPUT
+        echo "base_version=$BASE_VERSION" >> $GITHUB_OUTPUT
+
+    - name: Update version in header file
+      run: |
+        BASE_VERSION="${{ steps.version.outputs.base_version }}"
+        IFS='.' read -r NEW_MAJOR NEW_MINOR NEW_PATCH <<< "$BASE_VERSION"
+
+        # Only update header file for non-prerelease versions
+        if [ "${{ steps.version.outputs.is_prerelease }}" = "false" ]; then
+          # Update version numbers in header file
+          sed -i "s/^#define XTENSOR_VERSION_MAJOR [0-9]*/#define XTENSOR_VERSION_MAJOR $NEW_MAJOR/" include/xtensor/core/xtensor_config.hpp
+          sed -i "s/^#define XTENSOR_VERSION_MINOR [0-9]*/#define XTENSOR_VERSION_MINOR $NEW_MINOR/" include/xtensor/core/xtensor_config.hpp
+          sed -i "s/^#define XTENSOR_VERSION_PATCH [0-9]*/#define XTENSOR_VERSION_PATCH $NEW_PATCH/" include/xtensor/core/xtensor_config.hpp
+
+          git config --local user.name "GitHub Action"
+          git add include/xtensor/core/xtensor_config.hpp
+          git commit -m "Release version ${{ steps.version.outputs.version }}"
+        else
+          echo "Skipping header file update for prerelease"
+          git config --local user.name "GitHub Action"
+        fi
+
+    - name: Create tag
+      run: |
+        git tag -a "${{ steps.version.outputs.version }}" -m "Release version ${{ steps.version.outputs.version }}"
+
+    - name: Push changes and tag
+      run: |
+        git push origin master
+        git push origin "${{ steps.version.outputs.version }}"
+
+    - name: Create GitHub Release
+      uses: elgohr/Github-Release-Action@v5
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      with:
+        title: Release ${{ steps.version.outputs.version }}
+        tag: ${{ steps.version.outputs.version }}
+        prerelease: ${{ steps.version.outputs.is_prerelease }}

From 51fe4e47804b787696b2b0930948f9e975cfd106 Mon Sep 17 00:00:00 2001
From: Alexis Placet <alexis.placet@quantstack.net>
Date: Thu, 27 Aug 2026 16:12:04 +0200
Subject: [PATCH 4/4] Update changelog generation

---
 .github/workflows/release.yaml | 46 +++++++++++++++++++++++++++++++++-
 1 file changed, 45 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index 6bab51cd6..f960a2a48 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -100,6 +100,50 @@ jobs:
         echo "version=$FINAL_VERSION" >> $GITHUB_OUTPUT
         echo "base_version=$BASE_VERSION" >> $GITHUB_OUTPUT
 
+    - name: Update changelog
+      if: steps.version.outputs.is_prerelease == 'false'
+      env:
+        VERSION: ${{ steps.version.outputs.version }}
+      run: |
+        python3 - <<'EOF'
+        import os, pathlib, re, subprocess
+
+        version = os.environ["VERSION"]
+        changelog = pathlib.Path("docs/source/changelog.rst")
+
+        # Last non-prerelease tag (tags are exactly Major.minor.patch)
+        tags = subprocess.check_output(
+            ["git", "tag", "-l", "[0-9]*.[0-9]*.[0-9]*", "--sort=-v:refname"],
+            text=True).strip().splitlines()
+        if not tags:
+            print("Error: no previous release tag found")
+            exit(1)
+        last_tag = tags[0]
+
+        # Commit subjects since the last release, oldest first
+        subjects = subprocess.check_output(
+            ["git", "log", "--no-merges", "--reverse", "--pretty=format:%s", f"{last_tag}..HEAD"],
+            text=True).strip().splitlines()
+
+        lines = [version, "------", ""]
+        for s in subjects:
+            m = re.match(r"^(.*?) \(#(\d+)\)$", s)
+            if m:
+                lines.append(f"- {m.group(1)}")
+                lines.append(f"  `# {m.group(2)} https://github.com/xtensor-stack/xtensor/pull/{m.group(2)}`")
+            else:
+                lines.append(f"- {s}")
+
+        text = changelog.read_text()
+        marker = "=========\n\n"
+        head, sep, tail = text.partition(marker)
+        if not sep:
+            print("Error: changelog header not found")
+            exit(1)
+        changelog.write_text(head + sep + "\n".join(lines) + "\n\n" + tail)
+        print(f"Added {len(subjects)} commits to changelog for version {version}")
+        EOF
+
     - name: Update version in header file
       run: |
         BASE_VERSION="${{ steps.version.outputs.base_version }}"
@@ -113,7 +157,7 @@ jobs:
           sed -i "s/^#define XTENSOR_VERSION_PATCH [0-9]*/#define XTENSOR_VERSION_PATCH $NEW_PATCH/" include/xtensor/core/xtensor_config.hpp
 
           git config --local user.name "GitHub Action"
-          git add include/xtensor/core/xtensor_config.hpp
+          git add include/xtensor/core/xtensor_config.hpp docs/source/changelog.rst
           git commit -m "Release version ${{ steps.version.outputs.version }}"
         else
           echo "Skipping header file update for prerelease"