build: add script to squash and merge PRs

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type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
report:
  - task: lint_filenames
    status: passed
  - task: lint_editorconfig
    status: passed
  - task: lint_markdown
    status: na
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    status: na
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    status: na
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    status: na
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  - task: lint_typescript_declarations
    status: na
  - task: lint_typescript_tests
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  - task: lint_license_headers
    status: passed
---

Author: Planeshifter

.github/workflows/scripts/merge_pr

@@ -0,0 +1,148 @@
+#!/bin/bash
+#/
+# @license Apache-2.0
+#
+# Copyright (c) 2025 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#/
+
+# Script to merge a pull request.
+#
+# Usage: merge_pr PR_NUMBER
+#
+# Arguments:
+#
+#   PR_NUMBER    Pull request number.
+#
+# Environment variables:
+#
+#   GITHUB_TOKEN   GitHub token for authentication.
+
+# Ensure that the exit status of pipelines is non-zero in the event that at least one of the commands in a pipeline fails:
+set -o pipefail
+
+
+# VARIABLES #
+
+# Get the pull request number:
+pr_number="$1"
+
+# GitHub API base URL:
+GITHUB_API_URL="https://api.github.com"
+
+# Repository owner and name:
+REPO_OWNER="stdlib-js"
+REPO_NAME="stdlib"
+
+# Exit codes:
+SUCCESS=0
+ERROR=1
+
+# Identifier for PR commit message comments:
+COMMENT_IDENTIFIER="<!-- PR_COMMIT_MESSAGE -->"
+
+
+# FUNCTIONS #
+
+# Error handler.
+on_error() {
+    echo "ERROR: $1" >&2
+    exit $ERROR
+}
+
+# Makes GitHub API requests.
+github_api() {
+    local method="$1"
+    local endpoint="$2"
+    local data="$3"
+
+    # Initialize an array to hold curl headers:
+    local headers=()
+
+    # If GITHUB_TOKEN is set, add the Authorization header:
+    if [ -n "$GITHUB_TOKEN" ]; then
+        headers+=("-H" "Authorization: token $GITHUB_TOKEN")
+    fi
+
+    # Determine the HTTP method and construct the curl command accordingly:
+    case "$method" in
+        GET)
+            curl -s "${headers[@]}" "$GITHUB_API_URL$endpoint"
+            ;;
+        POST)
+            # For POST requests, always set the Content-Type header:
+            headers+=("-H" "Content-Type: application/json")
+
+            # If data is provided, include it in the request:
+            if [ -n "$data" ]; then
+                curl -s -X POST "${headers[@]}" -d "$data" "$GITHUB_API_URL$endpoint"
+            else
+                # Handle cases where POST data is required but not provided:
+                echo "POST request requires data."
+                on_error "POST request requires data"
+            fi
+            ;;
+        *)
+            on_error "Invalid HTTP method: $method"
+            ;;
+    esac
+}
+
+# Main execution sequence.
+main() {
+    # Check if PR number is provided:
+    if [ -z "$pr_number" ]; then
+        on_error "PR number is required"
+    fi
+
+    # Fetch PR comments to look for commit message comment:
+    comments=$(github_api "GET" "/repos/$REPO_OWNER/$REPO_NAME/issues/$pr_number/comments")
+
+    # Look for the PR commit message comment with the identifier:
+    commit_message_comment=$(echo "$comments" | jq -r --arg id "$COMMENT_IDENTIFIER" '.[] | select(.body | contains($id)) | .body')
+
+    if [ -z "$commit_message_comment" ]; then
+        on_error "No PR commit message comment found for PR #$pr_number"
+    fi
+
+    # Extract commit message from the Markdown code block in the comment:
+    commit_message=$(echo "$commit_message_comment" | awk '/```text/{flag=1;next}/```/{flag=0}flag')
+
+    if [ -z "$commit_message" ]; then
+        on_error "Couldn't extract commit message from PR comment"
+    fi
+
+    # Extract subject (first line) and body (everything after the first line):
+    commit_subject=$(echo "$commit_message" | head -n 1)
+    commit_body=$(echo "$commit_message" | tail -n +2)
+    commit_body=$(echo "$commit_body" | awk 'NF {p=1} p') # Trim leading empty lines
+
+    if [ -z "$commit_subject" ]; then
+        on_error "Couldn't extract commit subject from PR commit message"
+    fi
+    if [ -z "$commit_body" ]; then
+        on_error "Couldn't extract commit body from PR commit message"
+    fi
+
+    # Squash and merge the PR with the extracted subject and body:
+    if ! gh pr merge "$pr_number" --admin --squash --subject "$commit_subject" --body "$commit_body"; then
+        on_error "Failed to merge PR #$pr_number"
+    fi
+
+    echo "Successfully merged PR #$pr_number"
+    exit $SUCCESS
+}
+
+# Call main with all command-line arguments:
+main "$@"