Merge pull request #3129 from otavio/issue-3104

[rust.git] / src / expr.rs

diff --git a/src/expr.rs b/src/expr.rs
index 82d2a43ad072bd33ab1315e32c46288e0f71225d..fbbc592e547228c2b1175bd008a7013ff8ea5017 100644 (file)
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -801,6 +801,20 @@ fn rewrite_single_line(
     }
 }
 
+/// Returns true if the last line of pat_str has leading whitespace and it is wider than the
+/// shape's indent.
+fn last_line_offsetted(start_column: usize, pat_str: &str) -> bool {
+    let mut leading_whitespaces = 0;
+    for c in pat_str.chars().rev() {
+        match c {
+            '\n' => break,
+            _ if c.is_whitespace() => leading_whitespaces += 1,
+            _ => leading_whitespaces = 0,
+        }
+    }
+    leading_whitespaces > start_column
+}
+
 impl<'a> ControlFlow<'a> {
     fn rewrite_pat_expr(
         &self,
@@ -885,7 +899,8 @@ fn rewrite_cond(
             .saturating_sub(constr_shape.used_width() + offset + brace_overhead);
         let force_newline_brace = (pat_expr_string.contains('\n')
             || pat_expr_string.len() > one_line_budget)
-            && !last_line_extendable(&pat_expr_string);
+            && (!last_line_extendable(&pat_expr_string)
+                || last_line_offsetted(shape.used_width(), &pat_expr_string));
 
         // Try to format if-else on single line.
         if self.allow_single_line
@@ -1816,12 +1831,7 @@ fn rewrite_unary_op(
     shape: Shape,
 ) -> Option<String> {
     // For some reason, an UnOp is not spanned like BinOp!
-    let operator_str = match op {
-        ast::UnOp::Deref => "*",
-        ast::UnOp::Not => "!",
-        ast::UnOp::Neg => "-",
-    };
-    rewrite_unary_prefix(context, operator_str, expr, shape)
+    rewrite_unary_prefix(context, ast::UnOp::to_string(op), expr, shape)
 }
 
 fn rewrite_assignment(
@@ -1982,3 +1992,29 @@ pub fn is_method_call(expr: &ast::Expr) -> bool {
         _ => false,
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::last_line_offsetted;
+
+    #[test]
+    fn test_last_line_offsetted() {
+        let lines = "one\n    two";
+        assert_eq!(last_line_offsetted(2, lines), true);
+        assert_eq!(last_line_offsetted(4, lines), false);
+        assert_eq!(last_line_offsetted(6, lines), false);
+
+        let lines = "one    two";
+        assert_eq!(last_line_offsetted(2, lines), false);
+        assert_eq!(last_line_offsetted(0, lines), false);
+
+        let lines = "\ntwo";
+        assert_eq!(last_line_offsetted(2, lines), false);
+        assert_eq!(last_line_offsetted(0, lines), false);
+
+        let lines = "one\n    two      three";
+        assert_eq!(last_line_offsetted(2, lines), true);
+        let lines = "one\n two      three";
+        assert_eq!(last_line_offsetted(2, lines), false);
+    }
+}