Change the way string values are interpreted from build.executable - now they must be quoted or otherwise escaped suitable for parsing by shlex.split.

2 files changed, 14 insertions, 4 deletions

diff --git a/setuptools/command/easy_install.py b/setuptools/command/easy_install.py
index 54a3bc3a..340b1fac 100755
--- a/setuptools/command/easy_install.py
+++ b/setuptools/command/easy_install.py
@@ -1882,15 +1882,16 @@ class CommandSpec(list):
 
     @classmethod
     def from_environment(cls):
-        return cls.from_string(cls._sys_executable())
+        return cls.from_string('"' + cls._sys_executable() + '"')
 
     @classmethod
     def from_string(cls, string):
         """
-        Construct a command spec from a simple string, assumed to represent
-        the full name to an executable.
+        Construct a command spec from a simple string representing a command
+        line parseable by shlex.split.
         """
-        return JythonCommandSpec.from_string(string) or cls([string])
+        items = shlex.split(string)
+        return JythonCommandSpec.from_string(string) or cls(items)
 
     def install_options(self, script_text):
         self.options = shlex.split(self._extract_options(script_text))
diff --git a/setuptools/tests/test_easy_install.py b/setuptools/tests/test_easy_install.py
index e1f06788..a3d5b0a9 100644
--- a/setuptools/tests/test_easy_install.py
+++ b/setuptools/tests/test_easy_install.py
@@ -505,3 +505,12 @@ class TestCommandSpec:
             cmd = CommandSpec.from_environment()
         assert len(cmd) == 1
         assert cmd.as_header().startswith('#!"')
+
+    def test_from_simple_string_uses_shlex(self):
+        """
+        In order to support `executable = /usr/bin/env my-python`, make sure
+        from_param invokes shlex on that input.
+        """
+        cmd = CommandSpec.from_param('/usr/bin/env my-python')
+        assert len(cmd) == 2
+        assert '"' not in cmd.as_header()