Fix parsing of variable without a value (theskumar#158)

bbc2 · theskumar · commit 1f973777ddf5 · 2018-12-14T14:14:17.000+05:30
In Python, `\s` also matches newlines. This would cause newlines to be consumed by the equal sign matcher, resulting in the next line being considered as a value. For instance, the following would be parsed as `[("FOO", "BAR=b")]` instead of [("FOO", ""), ("BAR", "b")]. ```bash FOO= BAR=b ``` Fixes theskumar#157.
diff --git a/dotenv/main.py b/dotenv/main.py
@@ -21,14 +21,14 @@
     r"""
         (
             \s*                     # leading whitespace
-            (?:export\s+)?          # export
+            (?:export{0}+)?         # export
 
             ( '[^']+'               # single-quoted key
             | [^=\#\s]+             # or unquoted key
             )?
 
             (?:
-                (?:\s*=\s*)         # equal sign
+                (?:{0}*={0}*)       # equal sign
 
                 ( '(?:\\'|[^'])*'   # single-quoted value
                 | "(?:\\"|[^"])*"   # or double-quoted value
@@ -40,7 +40,7 @@
             (?:\#[^\r\n]*)?         # comment
             (?:\r|\n|\r\n)?         # newline
         )
-    """,
+    """.format(r'[^\S\r\n]'),
     re.MULTILINE | re.VERBOSE,
 )
 
diff --git a/tests/test_core.py b/tests/test_core.py
@@ -63,6 +63,13 @@ def restore_os_environ():
             Binding(key="c", value="d", original="c=d"),
         ],
     ),
+    (
+        'a=\nb=c',
+        [
+            Binding(key="a", value='', original='a=\n'),
+            Binding(key="b", value='c', original="b=c"),
+        ]
+    ),
     (
         'a="\nb=c',
         [

Original file line number	Diff line number	Diff line change
`@@ -63,6 +63,13 @@ def restore_os_environ():`
`63`	`63`	`Binding(key="c", value="d", original="c=d"),`
`64`	`64`	`],`
`65`	`65`	`),`
	`66`	`+ (`
	`67`	`+ 'a=\nb=c',`
	`68`	`+ [`
	`69`	`+ Binding(key="a", value='', original='a=\n'),`
	`70`	`+ Binding(key="b", value='c', original="b=c"),`
	`71`	`+ ]`
	`72`	`+ ),`
`66`	`73`	`(`
`67`	`74`	`'a="\nb=c',`
`68`	`75`	`[`