move single_char_pattern tests

tests/ui/methods.rs

@@ -498,46 +498,6 @@ fn clone_on_double_ref() {
     println!("{:p} {:p}",*y, z);
 }
 
-fn single_char_pattern() {
-    let x = "foo";
-    x.split("x");
-    x.split("xx");
-    x.split('x');
-
-    let y = "x";
-    x.split(y);
-    // Not yet testing for multi-byte characters
-    // Changing `r.len() == 1` to `r.chars().count() == 1` in `lint_single_char_pattern`
-    // should have done this but produced an ICE
-    //
-    // We may not want to suggest changing these anyway
-    // See: https://github.com/rust-lang-nursery/rust-clippy/issues/650#issuecomment-184328984
-    x.split("ß");
-    x.split("ℝ");
-    x.split("💣");
-    // Can't use this lint for unicode code points which don't fit in a char
-    x.split("❤️");
-    x.contains("x");
-    x.starts_with("x");
-    x.ends_with("x");
-    x.find("x");
-    x.rfind("x");
-    x.rsplit("x");
-    x.split_terminator("x");
-    x.rsplit_terminator("x");
-    x.splitn(0, "x");
-    x.rsplitn(0, "x");
-    x.matches("x");
-    x.rmatches("x");
-    x.match_indices("x");
-    x.rmatch_indices("x");
-    x.trim_left_matches("x");
-    x.trim_right_matches("x");
-
-    let h = HashSet::<String>::new();
-    h.contains("X"); // should not warn
-}
-
 #[allow(result_unwrap_used)]
 fn temporary_cstring() {
     use std::ffi::CString;

tests/ui/methods.stderr

@@ -627,128 +627,24 @@ error: using `clone` on a double-reference; this will copy the reference instead
     |
     = note: `-D clone-double-ref` implied by `-D warnings`
 
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:503:13
-    |
-503 |     x.split("x");
-    |     --------^^^- help: try using a char instead: `x.split('x')`
-    |
-    = note: `-D single-char-pattern` implied by `-D warnings`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:520:16
-    |
-520 |     x.contains("x");
-    |     -----------^^^- help: try using a char instead: `x.contains('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:521:19
-    |
-521 |     x.starts_with("x");
-    |     --------------^^^- help: try using a char instead: `x.starts_with('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:522:17
-    |
-522 |     x.ends_with("x");
-    |     ------------^^^- help: try using a char instead: `x.ends_with('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:523:12
-    |
-523 |     x.find("x");
-    |     -------^^^- help: try using a char instead: `x.find('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:524:13
-    |
-524 |     x.rfind("x");
-    |     --------^^^- help: try using a char instead: `x.rfind('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:525:14
-    |
-525 |     x.rsplit("x");
-    |     ---------^^^- help: try using a char instead: `x.rsplit('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:526:24
-    |
-526 |     x.split_terminator("x");
-    |     -------------------^^^- help: try using a char instead: `x.split_terminator('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:527:25
-    |
-527 |     x.rsplit_terminator("x");
-    |     --------------------^^^- help: try using a char instead: `x.rsplit_terminator('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:528:17
-    |
-528 |     x.splitn(0, "x");
-    |     ------------^^^- help: try using a char instead: `x.splitn(0, 'x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:529:18
-    |
-529 |     x.rsplitn(0, "x");
-    |     -------------^^^- help: try using a char instead: `x.rsplitn(0, 'x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:530:15
-    |
-530 |     x.matches("x");
-    |     ----------^^^- help: try using a char instead: `x.matches('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:531:16
-    |
-531 |     x.rmatches("x");
-    |     -----------^^^- help: try using a char instead: `x.rmatches('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:532:21
-    |
-532 |     x.match_indices("x");
-    |     ----------------^^^- help: try using a char instead: `x.match_indices('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:533:22
-    |
-533 |     x.rmatch_indices("x");
-    |     -----------------^^^- help: try using a char instead: `x.rmatch_indices('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:534:25
-    |
-534 |     x.trim_left_matches("x");
-    |     --------------------^^^- help: try using a char instead: `x.trim_left_matches('x')`
-
-error: single-character string constant used as pattern
-   --> $DIR/methods.rs:535:26
-    |
-535 |     x.trim_right_matches("x");
-    |     ---------------------^^^- help: try using a char instead: `x.trim_right_matches('x')`
-
 error: you are getting the inner pointer of a temporary `CString`
-   --> $DIR/methods.rs:545:5
+   --> $DIR/methods.rs:505:5
     |
-545 |     CString::new("foo").unwrap().as_ptr();
+505 |     CString::new("foo").unwrap().as_ptr();
     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     |
     = note: `-D temporary-cstring-as-ptr` implied by `-D warnings`
     = note: that pointer will be invalid outside this expression
 help: assign the `CString` to a variable to extend its lifetime
-   --> $DIR/methods.rs:545:5
+   --> $DIR/methods.rs:505:5
     |
-545 |     CString::new("foo").unwrap().as_ptr();
+505 |     CString::new("foo").unwrap().as_ptr();
     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: called `cloned().collect()` on a slice to create a `Vec`. Calling `to_vec()` is both faster and more readable
-   --> $DIR/methods.rs:550:27
+   --> $DIR/methods.rs:510:27
     |
-550 |     let v2 : Vec<isize> = v.iter().cloned().collect();
+510 |     let v2 : Vec<isize> = v.iter().cloned().collect();
     |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
     |
     = note: `-D iter-cloned-collect` implied by `-D warnings`

tests/ui/single_char_pattern.rs

@@ -0,0 +1,41 @@
+use std::collections::HashSet;
+
+fn main() {
+    let x = "foo";
+    x.split("x");
+    x.split("xx");
+    x.split('x');
+
+    let y = "x";
+    x.split(y);
+    // Not yet testing for multi-byte characters
+    // Changing `r.len() == 1` to `r.chars().count() == 1` in `lint_single_char_pattern`
+    // should have done this but produced an ICE
+    //
+    // We may not want to suggest changing these anyway
+    // See: https://github.com/rust-lang-nursery/rust-clippy/issues/650#issuecomment-184328984
+    x.split("ß");
+    x.split("ℝ");
+    x.split("💣");
+    // Can't use this lint for unicode code points which don't fit in a char
+    x.split("❤️");
+    x.contains("x");
+    x.starts_with("x");
+    x.ends_with("x");
+    x.find("x");
+    x.rfind("x");
+    x.rsplit("x");
+    x.split_terminator("x");
+    x.rsplit_terminator("x");
+    x.splitn(0, "x");
+    x.rsplitn(0, "x");
+    x.matches("x");
+    x.rmatches("x");
+    x.match_indices("x");
+    x.rmatch_indices("x");
+    x.trim_left_matches("x");
+    x.trim_right_matches("x");
+
+    let h = HashSet::<String>::new();
+    h.contains("X"); // should not warn
+}

tests/ui/single_char_pattern.stderr

@@ -0,0 +1,104 @@
+error: single-character string constant used as pattern
+ --> $DIR/single_char_pattern.rs:5:13
+  |
+5 |     x.split("x");
+  |     --------^^^- help: try using a char instead: `x.split('x')`
+  |
+  = note: `-D single-char-pattern` implied by `-D warnings`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:22:16
+   |
+22 |     x.contains("x");
+   |     -----------^^^- help: try using a char instead: `x.contains('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:23:19
+   |
+23 |     x.starts_with("x");
+   |     --------------^^^- help: try using a char instead: `x.starts_with('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:24:17
+   |
+24 |     x.ends_with("x");
+   |     ------------^^^- help: try using a char instead: `x.ends_with('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:25:12
+   |
+25 |     x.find("x");
+   |     -------^^^- help: try using a char instead: `x.find('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:26:13
+   |
+26 |     x.rfind("x");
+   |     --------^^^- help: try using a char instead: `x.rfind('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:27:14
+   |
+27 |     x.rsplit("x");
+   |     ---------^^^- help: try using a char instead: `x.rsplit('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:28:24
+   |
+28 |     x.split_terminator("x");
+   |     -------------------^^^- help: try using a char instead: `x.split_terminator('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:29:25
+   |
+29 |     x.rsplit_terminator("x");
+   |     --------------------^^^- help: try using a char instead: `x.rsplit_terminator('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:30:17
+   |
+30 |     x.splitn(0, "x");
+   |     ------------^^^- help: try using a char instead: `x.splitn(0, 'x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:31:18
+   |
+31 |     x.rsplitn(0, "x");
+   |     -------------^^^- help: try using a char instead: `x.rsplitn(0, 'x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:32:15
+   |
+32 |     x.matches("x");
+   |     ----------^^^- help: try using a char instead: `x.matches('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:33:16
+   |
+33 |     x.rmatches("x");
+   |     -----------^^^- help: try using a char instead: `x.rmatches('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:34:21
+   |
+34 |     x.match_indices("x");
+   |     ----------------^^^- help: try using a char instead: `x.match_indices('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:35:22
+   |
+35 |     x.rmatch_indices("x");
+   |     -----------------^^^- help: try using a char instead: `x.rmatch_indices('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:36:25
+   |
+36 |     x.trim_left_matches("x");
+   |     --------------------^^^- help: try using a char instead: `x.trim_left_matches('x')`
+
+error: single-character string constant used as pattern
+  --> $DIR/single_char_pattern.rs:37:26
+   |
+37 |     x.trim_right_matches("x");
+   |     ---------------------^^^- help: try using a char instead: `x.trim_right_matches('x')`
+