build: add long project description to wheel metadata

The wheel was missing the long description (the review thread's other
fields were already restored). Add it via pyproject [project].readme
(inline text), emitted by build_distrib.py — reusing the concise blurb
the old setuptools build shipped, not the full README.

Author: linesight

pyproject.toml

@@ -11,6 +11,7 @@ dynamic = ["version"]
 requires-python = ">=3.10"
 license = { text = "BSD-3-Clause" }
 description = "Python bindings for the Chromium Embedded Framework"
+readme = { text = "CEF Python is an open source project founded by Czarek Tomczak in 2012 to provide python bindings for the Chromium Embedded Framework. Examples of embedding CEF browser are available for many popular GUI toolkits including: wxPython, PyQt, PySide, Kivy, Panda3D, PyGTK, PyGObject, PyGame/PyOpenGL and PyWin32.\n\nThere are many use cases for CEF. You can embed a web browser control based on Chromium with great HTML 5 support. You can use it to create a HTML 5 based GUI in an application, this can act as a replacement for standard GUI toolkits like wxWidgets, Qt or GTK. You can render web content off-screen in application that use custom drawing frameworks. You can use it for automated testing of existing applications. You can use it for web scraping or as a web crawler, or other kind of internet bots.\n\nProject website:\nhttps://github.com/cztomczak/cefpython", content-type = "text/plain" }
 authors = [
     { name = "Czarek Tomczak", email = "czarek.tomczak@gmail.com" },
 ]

tools/build_distrib.py

@@ -196,7 +196,29 @@ def _core_metadata(version, project):
     for classifier in project.get("classifiers", []):
         lines.append("Classifier: " + classifier)
 
-    return ("\n".join(lines) + "\n").encode("utf-8")
+    # Long description (Description body). PEP 621 readme: a table with an
+    # inline "text" (+ "content-type") or a "file", or a bare filename string.
+    body = ""
+    readme = project.get("readme")
+    if isinstance(readme, dict):
+        content_type = readme.get("content-type", "text/plain")
+        if readme.get("text"):
+            body = readme["text"]
+        elif readme.get("file"):
+            with open(readme["file"], encoding="utf-8") as f:
+                body = f.read()
+        if body:
+            lines.append("Description-Content-Type: " + content_type)
+    elif isinstance(readme, str):
+        with open(readme, encoding="utf-8") as f:
+            body = f.read()
+        lines.append("Description-Content-Type: text/markdown")
+
+    header = "\n".join(lines) + "\n"
+    # The description body follows the headers, separated by one blank line.
+    if body:
+        return (header + "\n" + body + "\n").encode("utf-8")
+    return header.encode("utf-8")
 
 
 def _reduce_package_size_issue262(pkg_dir):