Issue/3901

pipenv/cmdparse.py

@@ -1,10 +1,61 @@
 import itertools
 import re
 import shlex
-
+import os
 import six
 
 
+class UnixShellEnvironmentVariable(object):
+    """
+    This class provides an abstraction on
+    unix shell environment variables assignments.
+
+    It uses a set of regular expressions:
+
+    # ENV_VAR_NAME_REGEX matches the env var name, which requires:
+        - must not start with a number
+        - only letters, numbers and underscore allowed
+
+    # ENV_VAR_VALUE_REGEX matches a correct value for an env var:
+        - A value not enclosed in quote characters, must not start with "="
+        - A value enclosed in quotes, must end with the same quote character used to open.
+        - Carriage return and Newline are not allowed into the value.
+
+    # ENV_VAR_REGEX is a composition of the two previous regex:
+        - No spacing allowed before and after the equal sign.
+    """
+
+    ENV_VAR_NAME_REGEX = r"([a-zA-Z_]+[a-zA-Z_0-9]*)"
+    ENV_VAR_VALUE_REGEX = r"((\"((?:[^\r\n\"\\]|\\.)*)\")|('((?:[^\r\n'\\]|\\.)*)')|([^=\"\'\r\n][^\"\'\r\n]*))"
+    ENV_VAR_REGEX = r"^{name_rgx}={value_rgx}".format(
+        name_rgx=ENV_VAR_NAME_REGEX,
+        value_rgx=ENV_VAR_VALUE_REGEX
+    )
+
+    def __init__(self, full_expr, name, value):
+        self.full_expr = full_expr
+        self.name = name
+        self.value = value
+
+    @classmethod
+    def parse(cls, env_var_assignment):
+        m = re.match(cls.ENV_VAR_REGEX, env_var_assignment)
+        if not m:
+            raise ValueError("The value '{}' didn't match the ENV_VAR_REGEX!".format(env_var_assignment))
+
+        return cls(
+            m.group(0),
+            m.group(1),
+            (m.group(4) or m.group(6) or m.group(7))
+        )
+
+    def name(self):
+        return self.name
+
+    def value(self):
+        return self.value
+
+
 class ScriptEmptyError(ValueError):
     pass
 
@@ -21,18 +72,38 @@ class Script(object):
     This always works in POSIX mode, even on Windows.
     """
 
-    def __init__(self, command, args=None):
+    def __init__(self, command, args=None, env_vars=None):
         self._parts = [command]
         if args:
             self._parts.extend(args)
 
+        for env_var in env_vars:
+            os.environ.putenv(
+                env_var.name(),
+                env_var.value()
+            )
+
     @classmethod
     def parse(cls, value):
         if isinstance(value, six.string_types):
             value = shlex.split(value)
         if not value:
             raise ScriptEmptyError(value)
-        return cls(value[0], value[1:])
+
+        env_vars = []
+        for el in value:
+            try:
+                env_var = UnixShellEnvironmentVariable.parse(el)
+                env_vars.append(env_var)
+                value.remove(el)
+            except ValueError:
+                pass
+
+        return cls(
+            value[0],
+            args=value[1:],
+            env_vars=env_vars,
+        )
 
     def __repr__(self):
         return "Script({0!r})".format(self._parts)