Don't return empty slice on last iteration with matched terminator. T…

…est reverse iteration.
rust-lang · Feb 9, 2020 · 5c9dc57 · 5c9dc57
1 parent 86bf962
commit 5c9dc57
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Showing 4 changed files with 255 additions and 132 deletions.
diff --git a/src/liballoc/tests/slice.rs b/src/liballoc/tests/slice.rs
@@ -859,18 +859,78 @@ fn test_splitator_inclusive() {
     assert_eq!(xs.split_inclusive(|x| *x % 2 == 0).collect::<Vec<_>>(), splits);
     let splits: &[&[_]] = &[&[1], &[2, 3, 4, 5]];
     assert_eq!(xs.split_inclusive(|x| *x == 1).collect::<Vec<_>>(), splits);
-    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5], &[]];
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
     assert_eq!(xs.split_inclusive(|x| *x == 5).collect::<Vec<_>>(), splits);
     let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
     assert_eq!(xs.split_inclusive(|x| *x == 10).collect::<Vec<_>>(), splits);
-    let splits: &[&[_]] = &[&[1], &[2], &[3], &[4], &[5], &[]];
+    let splits: &[&[_]] = &[&[1], &[2], &[3], &[4], &[5]];
     assert_eq!(xs.split_inclusive(|_| true).collect::<Vec<&[i32]>>(), splits);
 
     let xs: &[i32] = &[];
     let splits: &[&[i32]] = &[&[]];
     assert_eq!(xs.split_inclusive(|x| *x == 5).collect::<Vec<&[i32]>>(), splits);
 }
 
+#[test]
+fn test_splitator_inclusive_reverse() {
+    let xs = &[1, 2, 3, 4, 5];
+
+    let splits: &[&[_]] = &[&[5], &[3, 4], &[1, 2]];
+    assert_eq!(xs.split_inclusive(|x| *x % 2 == 0).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[2, 3, 4, 5], &[1]];
+    assert_eq!(xs.split_inclusive(|x| *x == 1).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive(|x| *x == 10).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[5], &[4], &[3], &[2], &[1]];
+    assert_eq!(xs.split_inclusive(|_| true).rev().collect::<Vec<_>>(), splits);
+
+    let xs: &[i32] = &[];
+    let splits: &[&[i32]] = &[&[]];
+    assert_eq!(xs.split_inclusive(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
+}
+
+#[test]
+fn test_splitator_mut_inclusive() {
+    let xs = &mut [1, 2, 3, 4, 5];
+
+    let splits: &[&[_]] = &[&[1, 2], &[3, 4], &[5]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x % 2 == 0).collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1], &[2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 1).collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 5).collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 10).collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1], &[2], &[3], &[4], &[5]];
+    assert_eq!(xs.split_inclusive_mut(|_| true).collect::<Vec<_>>(), splits);
+
+    let xs: &mut [i32] = &mut [];
+    let splits: &[&[i32]] = &[&[]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 5).collect::<Vec<_>>(), splits);
+}
+
+#[test]
+fn test_splitator_mut_inclusive_reverse() {
+    let xs = &mut [1, 2, 3, 4, 5];
+
+    let splits: &[&[_]] = &[&[5], &[3, 4], &[1, 2]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x % 2 == 0).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[2, 3, 4, 5], &[1]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 1).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 10).rev().collect::<Vec<_>>(), splits);
+    let splits: &[&[_]] = &[&[5], &[4], &[3], &[2], &[1]];
+    assert_eq!(xs.split_inclusive_mut(|_| true).rev().collect::<Vec<_>>(), splits);
+
+    let xs: &mut [i32] = &mut [];
+    let splits: &[&[i32]] = &[&[]];
+    assert_eq!(xs.split_inclusive_mut(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
+}
+
 #[test]
 fn test_splitnator() {
     let xs = &[1, 2, 3, 4, 5];

diff --git a/src/liballoc/tests/str.rs b/src/liballoc/tests/str.rs
@@ -1252,18 +1252,43 @@ fn test_split_char_iterator_inclusive() {
     let data = "\nMäry häd ä little lämb\nLittle lämb\n";
 
     let split: Vec<&str> = data.split_inclusive('\n').collect();
-    assert_eq!(split, ["\n", "Märy häd ä little lämb\n", "Little lämb\n", ""]);
+    assert_eq!(split, ["\n", "Märy häd ä little lämb\n", "Little lämb\n"]);
 
     let uppercase_separated = "SheePSharKTurtlECaT";
     let mut first_char = true;
-    let split: Vec<&str> = uppercase_separated.split_inclusive(|c: char| {
-        let split = !first_char && c.is_uppercase();
-        first_char = split;
-        split
-    }).collect();
-    assert_eq!(split, ["SheeP", "SharK", "TurtlE", "CaT", ""]);
+    let split: Vec<&str> = uppercase_separated
+        .split_inclusive(|c: char| {
+            let split = !first_char && c.is_uppercase();
+            first_char = split;
+            split
+        })
+        .collect();
+    assert_eq!(split, ["SheeP", "SharK", "TurtlE", "CaT"]);
 }
 
+#[test]
+fn test_split_char_iterator_inclusive_rev() {
+    let data = "\nMäry häd ä little lämb\nLittle lämb\n";
+
+    let split: Vec<&str> = data.split_inclusive('\n').rev().collect();
+    assert_eq!(split, ["Little lämb\n", "Märy häd ä little lämb\n", "\n"]);
+
+    // Note that the predicate is stateful and thus dependent
+    // on the iteration order.
+    // (A different predicate is needed for reverse iterator vs normal iterator.)
+    // Not sure if anything can be done though.
+    let uppercase_separated = "SheePSharKTurtlECaT";
+    let mut term_char = true;
+    let split: Vec<&str> = uppercase_separated
+        .split_inclusive(|c: char| {
+            let split = term_char && c.is_uppercase();
+            term_char = c.is_uppercase();
+            split
+        })
+        .rev()
+        .collect();
+    assert_eq!(split, ["CaT", "TurtlE", "SharK", "SheeP"]);
+}
 
 #[test]
 fn test_rsplit() {