Merge pull request #4512 from mwichmann/print-Variables

Allow printing a Variables object

Author: bdbaddog

CHANGES.txt

@@ -38,6 +38,8 @@ RELEASE  VERSION/DATE TO BE FILLED IN LATER
       by adding SKIP_PDF=1.  This should help with distro packaging of SCons,
       which now does not need "fop" and other tools to be set up in order to
       build pdf versions which are then ignored.
+    - Add the ability to print a Variables object for debugging purposes
+      (provides a __str__ method in the class).
 
 
 RELEASE 4.7.0 -  Sun, 17 Mar 2024 17:22:20 -0700

SCons/Variables/__init__.py

@@ -76,10 +76,21 @@ def __init__(self, files=None, args=None, is_global: bool=True) -> None:
             if not Variables.instance:
                 Variables.instance=self
 
+    def __str__(self) -> str:
+        """Provide a way to "print" a Variables object."""
+        s = "Variables(\n  options=[\n"
+        for option in self.options:
+            s += f"    {str(option)},\n"
+        s += "  ],\n"
+        s += f"  args={self.args},\n  files={self.files},\n  unknown={self.unknown},\n)"
+        return s
+
     def _do_add(self, key, help: str="", default=None, validator=None, converter=None, **kwargs) -> None:
 
         class Variable:
-            pass
+            def __str__(self) -> str:
+                """Provide a way to "print" a Variable object."""
+                return f"({self.key!r}, {self.aliases}, {self.help!r}, {self.default!r}, {self.validator}, {self.converter})"
 
         option = Variable()