Update gh-pages script and adjust HTML header.

Author: krilnon

Sources/TSPL/TSPL.docc/TSPL.md

@@ -1,7 +1,7 @@
-# ``TSPL``
+# The Swift Programming Language
 
 @Metadata {
-  @DisplayName("The Swift Programming Language")
+  @TechnologyRoot
 }
 
 @Options(scope: global) {

Sources/TSPL/TSPL.docc/header.html

@@ -0,0 +1,23 @@
+<!--
+  This source file is part of the Swift.org open source project
+
+  Copyright (c) 2022 Apple Inc. and the Swift project authors
+  Licensed under Apache License v2.0 with Runtime Library Exception
+
+  See https://swift.org/LICENSE.txt for license information
+  See https://swift.org/CONTRIBUTORS.txt for Swift project authors
+-->
+<header id="header" role="banner">
+    <div class="container">
+        <aside style="border-radius: 20px; border: 2px solid goldenrod; background: rgba(230, 241, 69, 0.625); padding: 5px; margin: 5px;">
+        <h3>Important</h3>
+        <p>
+            This is the development version of <em>The Swift Programming Language</em> book.
+        </p>
+        <p>
+            For the current shipping book, see <a href="https://docs.swift.org/swift-book/">swift.org</a>.
+            To contribute to its development, see the <a href="https://www.swift.org/documentation-workgroup/">Swift Documentation Workgroup</a>.
+        </p>
+        </aside>
+    </div>
+</header>

bin/update-book-preview

@@ -0,0 +1,70 @@
+#!/bin/bash
+#
+# This source file is part of the Swift.org open source project
+#
+# Copyright (c) 2022 Apple Inc. and the Swift project authors
+# Licensed under Apache License v2.0 with Runtime Library Exception
+#
+# See https://swift.org/LICENSE.txt for license information
+# See https://swift.org/CONTRIBUTORS.txt for Swift project authors
+#
+# Updates the GitHub Pages documentation site thats published from the 'docs'
+# subdirectory in the 'gh-pages' branch of this repository.
+#
+# This script should be run by someone with commit access to the 'gh-pages' branch
+# at a regular frequency so that the documentation content on the GitHub Pages site
+# is up-to-date with the content in this repo.
+#
+
+set -eu
+
+# A `realpath` alternative using the default C implementation.
+filepath() {
+  [[ $1 = /* ]] && echo "$1" || echo "$PWD/${1#./}"
+}
+
+SWIFT_BOOK_ROOT="$(dirname $(dirname $(filepath $0)))"
+
+# Set current directory to the repository root
+cd "$SWIFT_BOOK_ROOT"
+
+# Use git worktree to checkout the gh-pages branch of this repository in a gh-pages sub-directory
+git fetch
+git worktree add --checkout gh-pages origin/gh-pages
+
+# Pretty print DocC JSON output so that it can be consistently diffed between commits
+export DOCC_JSON_PRETTYPRINT="YES"
+
+# Generate documentation for TSPL and output it
+# to the /docs subdirectory in the gh-pages worktree directory.
+export SWIFTPM_ENABLE_COMMAND_PLUGINS=1
+swift package \
+    --allow-writing-to-directory "$SWIFT_BOOK_ROOT/gh-pages/docs" \
+    generate-documentation \
+    --target TSPL \
+    --disable-indexing \
+    --transform-for-static-hosting \
+    --experimental-enable-custom-templates \
+    --hosting-base-path swift-book \
+    --output-path "$SWIFT_BOOK_ROOT/gh-pages/docs"
+
+# Save the current commit we've just built documentation from in a variable
+CURRENT_COMMIT_HASH=`git rev-parse --short HEAD`
+
+# Commit and push our changes to the gh-pages branch
+cd gh-pages
+git add docs
+
+if [ -n "$(git status --porcelain)" ]; then
+    echo "Documentation changes found. Commiting the changes to the 'gh-pages' branch and pushing to origin."
+    git commit -m "Update GitHub Pages documentation site to '$CURRENT_COMMIT_HASH'."
+    git push origin HEAD:gh-pages
+else
+  # No changes found, nothing to commit.
+  echo "No documentation changes found."
+fi
+
+# Delete the git worktree we created
+cd ..
+exit
+git worktree remove gh-pages