cmds.projects.lib.templates: Add module

Add tmpl_render(), a function to provide a primitive template renderer. It takes a dictionary for values to replace variables shaped {some-variable} in templates found by their name. For now, the templates are defined in the templates module instead of being read from a template directory. The values may be lists, in which case they are rendered with a delimiter, defaulting to ",".
Using an existing template engine like jinja2 is tempting but would introduce additional dependencies jw-pkg is trying hard to avoid.
Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/cmds/projects/lib/templates.py

@@ -0,0 +1,73 @@
+import textwrap
+
+def format_lines(template, values, li_quote, li_delimiter):
+
+    def __format_value(val):
+        if not li_quote:
+            return str(val)
+        return f'"{val}"'
+
+    for key, value in values.items():
+        if isinstance(value, (list, tuple)):
+            values[key] = li_delimiter.join(map(__format_value, value))
+
+    ret = []
+    parts = template.splitlines(keepends = True)
+
+    for line in parts:
+        for key, value in values.items():
+            marker = '{' + key + '}'
+            if marker in line:
+                indent = line[:line.index(marker)]
+                value = str(value).replace('\n', '\n' + indent)
+                line = line.replace(marker, value)
+        ret.append(line)
+
+    return ''.join(ret)
+
+_templates = {
+    'pkg-config':
+    """\
+        prefix = {prefix}
+        exec_prefix = {{prefix}}
+        includedir = {{prefix}}/include
+        libdir = {{exec_prefix}}/lib
+
+        Name: {name}
+        Description: {description}
+        Version: {version}
+        """,
+    'pyrightconfig.json':
+    """\
+        {
+          "extends": {base},
+          "include": [
+            {include}
+          ],
+          "exclude": [
+            "**/__pycache__",
+            "**/.pytest_cache",
+            "**/.mypy_cache",
+            "**/.ruff_cache",
+            "**/.venv",
+            "**/build",
+            "**/dist"
+          ],
+          "extraPaths": [
+            {extra_paths}
+          ],
+          "typeCheckingMode": "basic",
+          "pythonPlatform": "Linux"
+        }
+        """,
+}
+
+def tmpl_render(
+    template_name: str, values, li_quote = False, li_delimiter = '\n'
+) -> str:
+    return format_lines(
+        textwrap.dedent(_templates[template_name]),
+        values,
+        li_quote = li_quote,
+        li_delimiter = li_delimiter,
+    )