Split ternary expressions

Fixes #141

diff --git a/README.md b/README.md
index 02cf2f92a7646af06ad284f8ef1e3690c5280383..4663176726b668c45fc80ff0b12430e651af230c 100644 (file)
--- a/README.md
+++ b/README.md
@@ -540,6 +540,8 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 
 * fixed invalid splitting on comma in lambda arguments (#133)
 
+* fixed missing splits of ternary expressions (#141)
+
 ### 18.4a2
 
 * fixed parsing of unaligned standalone comments (#99, #112)

diff --git a/black.py b/black.py
index aeb740226f3ee4461c7d7b81f361634d63835b07..5bf466af91c5e0eb03f293621ab00346dcfc00c3 100644 (file)
--- a/black.py
+++ b/black.py
@@ -583,6 +583,7 @@ UNPACKING_PARENTS = {
 }
 COMPREHENSION_PRIORITY = 20
 COMMA_PRIORITY = 10
+TERNARY_PRIORITY = 7
 LOGIC_PRIORITY = 5
 STRING_PRIORITY = 4
 COMPARATOR_PRIORITY = 3
@@ -1602,6 +1603,14 @@ def is_split_before_delimiter(leaf: Leaf, previous: Leaf = None) -> int:
     ):
         return COMPREHENSION_PRIORITY
 
+    if (
+        leaf.type == token.NAME
+        and leaf.value in {"if", "else"}
+        and leaf.parent
+        and leaf.parent.type == syms.test
+    ):
+        return TERNARY_PRIORITY
+
     if leaf.type == token.NAME and leaf.value in LOGIC_OPERATORS and leaf.parent:
         return LOGIC_PRIORITY
 

diff --git a/tests/expression.diff b/tests/expression.diff
index 9da00484c384d101bf8c088378ec8f4883c5572a..da48a13a1936c62f1fde517473eebc140a6e33a7 100644 (file)
--- a/tests/expression.diff
+++ b/tests/expression.diff
@@ -11,7 +11,7 @@
  True
  False
  1
-@@ -29,60 +29,78 @@
+@@ -29,61 +29,83 @@
  ~great
  +value
  -1
@@ -37,8 +37,14 @@
  (str or None) if True else (str or bytes or None)
  str or None if (1 if True else 2) else str or bytes or None
  (str or None) if (1 if True else 2) else (str or bytes or None)
+-((super_long_variable_name or None) if (1 if super_long_test_name else 2) else (str or bytes or None))
 -{'2.7': dead, '3.7': (long_live or die_hard)}
 -{'2.7': dead, '3.7': (long_live or die_hard), **{'3.6': verygood}}
++(
++    (super_long_variable_name or None)
++    if (1 if super_long_test_name else 2)
++    else (str or bytes or None)
++)
 +{"2.7": dead, "3.7": (long_live or die_hard)}
 +{"2.7": dead, "3.7": (long_live or die_hard), **{"3.6": verygood}}
  {**a, **b, **c}
@@ -110,7 +116,7 @@
  call(**self.screen_kwargs)
  call(b, **self.screen_kwargs)
  lukasz.langa.pl
-@@ -91,11 +109,11 @@
+@@ -92,11 +114,11 @@
  1.0 .real
  ....__class__
  list[str]
@@ -123,7 +129,7 @@
  ]
  slice[0]
  slice[0:1]
-@@ -122,88 +140,122 @@
+@@ -123,88 +145,122 @@
  numpy[-(c + 1):, d]
  numpy[:, l[-2]]
  numpy[:, ::-1]

diff --git a/tests/expression.py b/tests/expression.py
index c67505fc1fbf3d42370b2ab0b93bccabdbb29743..2c4d8ddbd75ca3d531a89c91231fc58b8dfeb9e2 100644 (file)
--- a/tests/expression.py
+++ b/tests/expression.py
@@ -43,6 +43,7 @@ str or None if True else str or bytes or None
 (str or None) if True else (str or bytes or None)
 str or None if (1 if True else 2) else str or bytes or None
 (str or None) if (1 if True else 2) else (str or bytes or None)
+((super_long_variable_name or None) if (1 if super_long_test_name else 2) else (str or bytes or None))
 {'2.7': dead, '3.7': (long_live or die_hard)}
 {'2.7': dead, '3.7': (long_live or die_hard), **{'3.6': verygood}}
 {**a, **b, **c}
@@ -260,6 +261,11 @@ str or None if True else str or bytes or None
 (str or None) if True else (str or bytes or None)
 str or None if (1 if True else 2) else str or bytes or None
 (str or None) if (1 if True else 2) else (str or bytes or None)
+(
+    (super_long_variable_name or None)
+    if (1 if super_long_test_name else 2)
+    else (str or bytes or None)
+)
 {"2.7": dead, "3.7": (long_live or die_hard)}
 {"2.7": dead, "3.7": (long_live or die_hard), **{"3.6": verygood}}
 {**a, **b, **c}