Upgrade smallvec to 1.10.0 am: db74ff043c

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/smallvec/+/2422379

Change-Id: I0d22cb7dc4724d1e2c1e7a103fd8137323b06465
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

12 files changed, 358 insertions, 28 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
index aa1c5bb..5d6626b 100644
--- a/.cargo_vcs_info.json
+++ b/.cargo_vcs_info.json
@@ -1,5 +1,6 @@
 {
   "git": {
-    "sha1": "0a4fdff3b012ed4d4b603800bf971239e5a966ba"
-  }
-}
+    "sha1": "3c77a35df6df29a1c516a59f1d04738432edf57f"
+  },
+  "path_in_vcs": ""
+}
\ No newline at end of file
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 6baaaea..467bf1f 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -7,12 +7,12 @@ on:
   workflow_dispatch:
 
 jobs:
-  linux-ci:
-    name: Linux
-    runs-on: ubuntu-latest
+  ci:
+    name: Build/Test
     strategy:
       matrix:
         toolchain: ["stable", "beta", "nightly", "1.36.0"]
+        os: [ubuntu-latest]
         include:
           - toolchain: stable
             env:
@@ -20,10 +20,16 @@ jobs:
           - toolchain: beta
             env:
               DO_FUZZ: 1
+          - os: windows-latest
+            toolchain: nightly
+
+    runs-on: ${{ matrix.os }}
+
     steps:
       - uses: actions/checkout@v2
 
       - name: Install packages
+        if: matrix.os == 'ubuntu-latest'
         run: sudo apt-get install -y binutils-dev libunwind8-dev libcurl4-openssl-dev libelf-dev libdw-dev cmake gcc libiberty-dev
 
       - name: Install toolchain
@@ -37,9 +43,11 @@ jobs:
         run: cargo build --verbose
 
       - name: Cargo test
+        if: matrix.toolchain != '1.36.0'
         run: cargo test --verbose
 
       - name: Cargo test w/ serde
+        if: matrix.toolchain != '1.36.0'
         run: cargo test --verbose --features serde
 
       - name: Cargo check w/o default features
@@ -50,6 +58,14 @@ jobs:
         if: matrix.toolchain == 'beta'
         run: cargo test --verbose --features union
 
+      - name: Cargo test w/ debugger_visualizer
+        if: matrix.toolchain == 'nightly'
+        run: cargo test --test debugger_visualizer --verbose --features debugger_visualizer -- --test-threads=1
+
+      - name: Cargo test w/ debugger_visualizer and union
+        if: matrix.toolchain == 'nightly'
+        run: cargo test --test debugger_visualizer --verbose --features 'debugger_visualizer,union' -- --test-threads=1
+
       - name: Cargo test all features
         if: matrix.toolchain == 'nightly'
         run: cargo test --verbose --all-features
@@ -59,8 +75,10 @@ jobs:
         run: cargo bench --verbose bench
 
       - name: miri
-        if: matrix.toolchain == 'nightly'
+        if: matrix.toolchain == 'nightly' && matrix.os == 'ubuntu-latest'
         run: bash ./scripts/run_miri.sh
+        env:
+          MIRIFLAGS: '-Zmiri-tag-raw-pointers'
 
       - name: fuzz
         if: env.DO_FUZZ == '1'
@@ -71,7 +89,7 @@ jobs:
     name: homu build finished
     runs-on: ubuntu-latest
     needs:
-      - "linux-ci"
+      - "ci"
 
     steps:
       - name: Mark the job as successful
diff --git a/Android.bp b/Android.bp
index c86cf0e..d13eba1 100644
--- a/Android.bp
+++ b/Android.bp
@@ -42,7 +42,7 @@ rust_library {
     host_supported: true,
     crate_name: "smallvec",
     cargo_env_compat: true,
-    cargo_pkg_version: "1.8.0",
+    cargo_pkg_version: "1.10.0",
     srcs: ["src/lib.rs"],
     edition: "2018",
     apex_available: [
diff --git a/Cargo.toml b/Cargo.toml
index 7ff65de..a365ca1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,18 +12,35 @@
 [package]
 edition = "2018"
 name = "smallvec"
-version = "1.8.0"
+version = "1.10.0"
 authors = ["The Servo Project Developers"]
 description = "'Small vector' optimization: store up to a small number of items on the stack"
 documentation = "https://docs.rs/smallvec/"
 readme = "README.md"
-keywords = ["small", "vec", "vector", "stack", "no_std"]
+keywords = [
+    "small",
+    "vec",
+    "vector",
+    "stack",
+    "no_std",
+]
 categories = ["data-structures"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 repository = "https://github.com/servo/rust-smallvec"
+
 [package.metadata.docs.rs]
 all-features = true
-rustdoc-args = ["--cfg", "docsrs"]
+rustdoc-args = [
+    "--cfg",
+    "docsrs",
+]
+
+[[test]]
+name = "debugger_visualizer"
+path = "tests/debugger_visualizer.rs"
+test = false
+required-features = ["debugger_visualizer"]
+
 [dependencies.arbitrary]
 version = "1"
 optional = true
@@ -32,12 +49,20 @@ optional = true
 version = "1"
 optional = true
 default-features = false
+
 [dev-dependencies.bincode]
 version = "1.0.1"
 
+[dev-dependencies.debugger_test]
+version = "0.1.0"
+
+[dev-dependencies.debugger_test_parser]
+version = "0.1.0"
+
 [features]
 const_generics = []
 const_new = ["const_generics"]
+debugger_visualizer = []
 may_dangle = []
 specialization = []
 union = []
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
index 605fdb3..90209b7 100644
--- a/Cargo.toml.orig
+++ b/Cargo.toml.orig
@@ -1,9 +1,9 @@
 [package]
 name = "smallvec"
-version = "1.8.0"
+version = "1.10.0"
 edition = "2018"
 authors = ["The Servo Project Developers"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 repository = "https://github.com/servo/rust-smallvec"
 description = "'Small vector' optimization: store up to a small number of items on the stack"
 keywords = ["small", "vec", "vector", "stack", "no_std"]
@@ -19,13 +19,30 @@ union = []
 specialization = []
 may_dangle = []
 
+# UNSTABLE FEATURES (requires Rust nightly)
+# Enable to use the #[debugger_visualizer] attribute.
+debugger_visualizer = []
+
 [dependencies]
 serde = { version = "1", optional = true, default-features = false }
 arbitrary = { version = "1", optional = true }
 
 [dev_dependencies]
 bincode = "1.0.1"
+debugger_test = "0.1.0"
+debugger_test_parser = "0.1.0"
 
 [package.metadata.docs.rs]
 all-features = true
 rustdoc-args = ["--cfg", "docsrs"]
+
+[[test]]
+name = "debugger_visualizer"
+path = "tests/debugger_visualizer.rs"
+required-features = ["debugger_visualizer"]
+# Do not run these tests by default. These tests need to
+# be run with the additional rustc flag `--test-threads=1`
+# since each test causes a debugger to attach to the current
+# test process. If multiple debuggers try to attach at the same
+# time, the test will fail.
+test = false
diff --git a/METADATA b/METADATA
index e726d44..3a50c0d 100644
--- a/METADATA
+++ b/METADATA
@@ -1,3 +1,7 @@
+# This project was upgraded with external_updater.
+# Usage: tools/external_updater/updater.sh update rust/crates/smallvec
+# For more info, check https://cs.android.com/android/platform/superproject/+/master:tools/external_updater/README.md
+
 name: "smallvec"
 description: "\'Small vector\' optimization: store up to a small number of items on the stack"
 third_party {
@@ -7,13 +11,13 @@ third_party {
   }
   url {
     type: ARCHIVE
-    value: "https://static.crates.io/crates/smallvec/smallvec-1.8.0.crate"
+    value: "https://static.crates.io/crates/smallvec/smallvec-1.10.0.crate"
   }
-  version: "1.8.0"
+  version: "1.10.0"
   license_type: NOTICE
   last_upgrade_date {
-    year: 2022
-    month: 3
-    day: 1
+    year: 2023
+    month: 2
+    day: 6
   }
 }
diff --git a/benches/bench.rs b/benches/bench.rs
index ad73226..b52ee15 100644
--- a/benches/bench.rs
+++ b/benches/bench.rs
@@ -96,6 +96,8 @@ make_benches! {
     SmallVec<[u64; VEC_SIZE]> {
         bench_push => gen_push(SPILLED_SIZE as _),
         bench_push_small => gen_push(VEC_SIZE as _),
+        bench_insert_push => gen_insert_push(SPILLED_SIZE as _),
+        bench_insert_push_small => gen_insert_push(VEC_SIZE as _),
         bench_insert => gen_insert(SPILLED_SIZE as _),
         bench_insert_small => gen_insert(VEC_SIZE as _),
         bench_remove => gen_remove(SPILLED_SIZE as _),
@@ -118,6 +120,8 @@ make_benches! {
     Vec<u64> {
         bench_push_vec => gen_push(SPILLED_SIZE as _),
         bench_push_vec_small => gen_push(VEC_SIZE as _),
+        bench_insert_push_vec => gen_insert_push(SPILLED_SIZE as _),
+        bench_insert_push_vec_small => gen_insert_push(VEC_SIZE as _),
         bench_insert_vec => gen_insert(SPILLED_SIZE as _),
         bench_insert_vec_small => gen_insert(VEC_SIZE as _),
         bench_remove_vec => gen_remove(SPILLED_SIZE as _),
@@ -151,6 +155,21 @@ fn gen_push<V: Vector<u64>>(n: u64, b: &mut Bencher) {
     });
 }
 
+fn gen_insert_push<V: Vector<u64>>(n: u64, b: &mut Bencher) {
+    #[inline(never)]
+    fn insert_push_noinline<V: Vector<u64>>(vec: &mut V, x: u64) {
+        vec.insert(x as usize, x);
+    }
+
+    b.iter(|| {
+        let mut vec = V::new();
+        for x in 0..n {
+            insert_push_noinline(&mut vec, x);
+        }
+        vec
+    });
+}
+
 fn gen_insert<V: Vector<u64>>(n: u64, b: &mut Bencher) {
     #[inline(never)]
     fn insert_noinline<V: Vector<u64>>(vec: &mut V, p: usize, x: u64) {
diff --git a/debug_metadata/README.md b/debug_metadata/README.md
new file mode 100644
index 0000000..1375008
--- /dev/null
+++ b/debug_metadata/README.md
@@ -0,0 +1,111 @@
+## Debugger Visualizers
+
+Many languages and debuggers enable developers to control how a type is
+displayed in a debugger. These are called "debugger visualizations" or "debugger
+views".
+
+The Windows debuggers (WinDbg\CDB) support defining custom debugger visualizations using
+the `Natvis` framework. To use Natvis, developers write XML documents using the natvis
+schema that describe how debugger types should be displayed with the `.natvis` extension.
+(See: https://docs.microsoft.com/en-us/visualstudio/debugger/create-custom-views-of-native-objects?view=vs-2019)
+The Natvis files provide patterns which match type names a description of how to display
+those types.
+
+The Natvis schema can be found either online (See: https://code.visualstudio.com/docs/cpp/natvis#_schema)
+or locally at `<VS Installation Folder>\Xml\Schemas\1033\natvis.xsd`.
+
+The GNU debugger (GDB) supports defining custom debugger views using Pretty Printers.
+Pretty printers are written as python scripts that describe how a type should be displayed
+when loaded up in GDB/LLDB. (See: https://sourceware.org/gdb/onlinedocs/gdb/Pretty-Printing.html#Pretty-Printing)
+The pretty printers provide patterns, which match type names, and for matching
+types, descibe how to display those types. (For writing a pretty printer, see: https://sourceware.org/gdb/onlinedocs/gdb/Writing-a-Pretty_002dPrinter.html#Writing-a-Pretty_002dPrinter).
+
+### Embedding Visualizers
+
+Through the use of the currently unstable `#[debugger_visualizer]` attribute, the `smallvec`
+crate can embed debugger visualizers into the crate metadata.
+
+Currently the two types of visualizers supported are Natvis and Pretty printers.
+
+For Natvis files, when linking an executable with a crate that includes Natvis files,
+the MSVC linker will embed the contents of all Natvis files into the generated `PDB`.
+
+For pretty printers, the compiler will encode the contents of the pretty printer
+in the `.debug_gdb_scripts` section of the `ELF` generated.
+
+### Testing Visualizers
+
+The `smallvec` crate supports testing debugger visualizers defined for this crate. The entry point for
+these tests are `tests/debugger_visualizer.rs`. These tests are defined using the `debugger_test` and
+`debugger_test_parser` crates. The `debugger_test` crate is a proc macro crate which defines a
+single proc macro attribute, `#[debugger_test]`. For more detailed information about this crate,
+see https://crates.io/crates/debugger_test. The CI pipeline for the `smallvec` crate has been updated
+to run the debugger visualizer tests to ensure debugger visualizers do not become broken/stale.
+
+The `#[debugger_test]` proc macro attribute may only be used on test functions and will run the
+function under the debugger specified by the `debugger` meta item.
+
+This proc macro attribute has 3 required values:
+
+1. The first required meta item, `debugger`, takes a string value which specifies the debugger to launch.
+2. The second required meta item, `commands`, takes a string of new line (`\n`) separated list of debugger
+commands to run.
+3. The third required meta item, `expected_statements`, takes a string of new line (`\n`) separated list of
+statements that must exist in the debugger output. Pattern matching through regular expressions is also
+supported by using the `pattern:` prefix for each expected statement.
+
+#### Example:
+
+```rust
+#[debugger_test(
+    debugger = "cdb",
+    commands = "command1\ncommand2\ncommand3",
+    expected_statements = "statement1\nstatement2\nstatement3")]
+fn test() {
+
+}
+```
+
+Using a multiline string is also supported, with a single debugger command/expected statement per line:
+
+```rust
+#[debugger_test(
+    debugger = "cdb",
+    commands = "
+command1
+command2
+command3",
+    expected_statements = "
+statement1
+pattern:statement[0-9]+
+statement3")]
+fn test() {
+    
+}
+```
+
+In the example above, the second expected statement uses pattern matching through a regular expression
+by using the `pattern:` prefix.
+
+#### Testing Locally
+
+Currently, only Natvis visualizations have been defined for the `smallvec` crate via `debug_metadata/smallvec.natvis`,
+which means the `tests/debugger_visualizer.rs` tests need to be run on Windows using the `*-pc-windows-msvc` targets.
+To run these tests locally, first ensure the debugging tools for Windows are installed or install them following
+the steps listed here, [Debugging Tools for Windows](https://docs.microsoft.com/en-us/windows-hardware/drivers/debugger/).
+Once the debugging tools have been installed, the tests can be run in the same manner as they are in the CI
+pipeline.
+
+#### Note
+
+When running the debugger visualizer tests, `tests/debugger_visualizer.rs`, they need to be run consecutively
+and not in parallel. This can be achieved by passing the flag `--test-threads=1` to rustc. This is due to
+how the debugger tests are run. Each test marked with the `#[debugger_test]` attribute launches a debugger
+and attaches it to the current test process. If tests are running in parallel, the test will try to attach
+a debugger to the current process which may already have a debugger attached causing the test to fail.
+
+For example:
+
+```
+cargo test --test debugger_visualizer --features debugger_visualizer -- --test-threads=1
+```
diff --git a/debug_metadata/smallvec.natvis b/debug_metadata/smallvec.natvis
new file mode 100644
index 0000000..b38d47c
--- /dev/null
+++ b/debug_metadata/smallvec.natvis
@@ -0,0 +1,35 @@
+<AutoVisualizer xmlns="http://schemas.microsoft.com/vstudio/debugger/natvis/2010">
+  <Type Name="smallvec::SmallVec&lt;array$&lt;*,*&gt;&gt;" Priority="Medium">
+    <Intrinsic Name="is_inline" Expression="$T2 &gt; capacity" />
+    <Intrinsic Name="len" Expression="is_inline() ? capacity : data.variant1.value.__0.__1" />
+    <Intrinsic Name="data_ptr" Expression="is_inline() ? data.variant0.value.__0.value.value : data.variant1.value.__0.__0" />
+
+    <DisplayString>{{ len={len()} }}</DisplayString>
+    <Expand>
+        <Item Name="[capacity]">is_inline() ? $T2 : capacity</Item>
+        <Item Name="[len]">len()</Item>
+
+        <ArrayItems>
+            <Size>len()</Size>
+            <ValuePointer>data_ptr()</ValuePointer>
+        </ArrayItems>
+    </Expand>
+  </Type>
+
+  <Type Name="smallvec::SmallVec&lt;array$&lt;*,*&gt;&gt;" Priority="MediumLow">
+    <Intrinsic Name="is_inline" Expression="$T2 &gt; capacity" />
+    <Intrinsic Name="len" Expression="is_inline() ? capacity : data.heap.__1" />
+    <Intrinsic Name="data_ptr" Expression="is_inline() ? data.inline.value.value.value : data.heap.__0" />
+
+    <DisplayString>{{ len={len()} }}</DisplayString>
+    <Expand>
+        <Item Name="[capacity]">is_inline() ? $T2 : capacity</Item>
+        <Item Name="[len]">len()</Item>
+
+        <ArrayItems>
+            <Size>len()</Size>
+            <ValuePointer>data_ptr()</ValuePointer>
+        </ArrayItems>
+    </Expand>
+  </Type>
+</AutoVisualizer>
\ No newline at end of file
diff --git a/scripts/run_miri.sh b/scripts/run_miri.sh
index 817928a..010ceb0 100644
--- a/scripts/run_miri.sh
+++ b/scripts/run_miri.sh
@@ -11,6 +11,7 @@ cargo clean
 
 MIRI_NIGHTLY=nightly-$(curl -s https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-gnu/miri)
 echo "Installing latest nightly with Miri: $MIRI_NIGHTLY"
+rustup override unset
 rustup default "$MIRI_NIGHTLY"
 
 rustup component add miri
@@ -19,3 +20,5 @@ cargo miri setup
 cargo miri test --verbose
 cargo miri test --verbose --features union
 cargo miri test --verbose --all-features
+
+rustup override set nightly
diff --git a/src/lib.rs b/src/lib.rs
index 1699a71..a335ca4 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -81,6 +81,11 @@
 #![cfg_attr(feature = "specialization", allow(incomplete_features))]
 #![cfg_attr(feature = "specialization", feature(specialization))]
 #![cfg_attr(feature = "may_dangle", feature(dropck_eyepatch))]
+#![cfg_attr(
+    feature = "debugger_visualizer",
+    feature(debugger_visualizer),
+    debugger_visualizer(natvis_file = "../debug_metadata/smallvec.natvis")
+)]
 #![deny(missing_docs)]
 
 #[doc(hidden)]
@@ -392,8 +397,11 @@ impl<'a, T: 'a + Array> Drop for Drain<'a, T> {
                 let start = source_vec.len();
                 let tail = self.tail_start;
                 if tail != start {
-                    let src = source_vec.as_ptr().add(tail);
-                    let dst = source_vec.as_mut_ptr().add(start);
+                    // as_mut_ptr creates a &mut, invalidating other pointers.
+                    // This pattern avoids calling it with a pointer already present.
+                    let ptr = source_vec.as_mut_ptr();
+                    let src = ptr.add(tail);
+                    let dst = ptr.add(start);
                     ptr::copy(src, dst, self.tail_len);
                 }
                 source_vec.set_len(start + self.tail_len);
@@ -813,13 +821,14 @@ impl<A: Array> SmallVec<A> {
         unsafe {
             self.set_len(start);
 
-            let range_slice = slice::from_raw_parts_mut(self.as_mut_ptr().add(start), end - start);
+            let range_slice = slice::from_raw_parts(self.as_ptr().add(start), end - start);
 
             Drain {
                 tail_start: end,
                 tail_len: len - end,
                 iter: range_slice.iter(),
-                vec: NonNull::from(self),
+                // Since self is a &mut, passing it to a function would invalidate the slice iterator.
+                vec: NonNull::new_unchecked(self as *mut _),
             }
         }
     }
@@ -1064,17 +1073,22 @@ impl<A: Array> SmallVec<A> {
 
     /// Insert an element at position `index`, shifting all elements after it to the right.
     ///
-    /// Panics if `index` is out of bounds.
+    /// Panics if `index > len`.
     pub fn insert(&mut self, index: usize, element: A::Item) {
         self.reserve(1);
 
         unsafe {
             let (mut ptr, len_ptr, _) = self.triple_mut();
             let len = *len_ptr;
-            assert!(index <= len);
-            *len_ptr = len + 1;
             ptr = ptr.add(index);
-            ptr::copy(ptr, ptr.add(1), len - index);
+            if index < len {
+                ptr::copy(ptr, ptr.add(1), len - index);
+            } else if index == len {
+                // No elements need shifting.
+            } else {
+                panic!("index exceeds length");
+            }
+            *len_ptr = len + 1;
             ptr::write(ptr, element);
         }
     }
@@ -1112,6 +1126,10 @@ impl<A: Array> SmallVec<A> {
                 len: old_len + lower_size_bound,
             };
 
+            // The set_len above invalidates the previous pointers, so we must re-create them.
+            let start = self.as_mut_ptr();
+            let ptr = start.add(index);
+
             while num_added < lower_size_bound {
                 let element = match iter.next() {
                     Some(x) => x,
@@ -1219,6 +1237,15 @@ impl<A: Array> SmallVec<A> {
         self.truncate(len - del);
     }
 
+    /// Retains only the elements specified by the predicate.
+    ///
+    /// This method is identical in behaviour to [`retain`]; it is included only
+    /// to maintain api-compatability with `std::Vec`, where the methods are
+    /// separate for historical reasons.
+    pub fn retain_mut<F: FnMut(&mut A::Item) -> bool>(&mut self, f: F) {
+        self.retain(f)
+    }
+
     /// Removes consecutive duplicate elements.
     pub fn dedup(&mut self)
     where
@@ -2062,6 +2089,7 @@ impl<T, const N: usize> SmallVec<[T; N]> {
 #[cfg_attr(docsrs, doc(cfg(feature = "const_generics")))]
 unsafe impl<T, const N: usize> Array for [T; N] {
     type Item = T;
+    #[inline]
     fn size() -> usize {
         N
     }
@@ -2073,6 +2101,7 @@ macro_rules! impl_array(
         $(
             unsafe impl<T> Array for [T; $size] {
                 type Item = T;
+                #[inline]
                 fn size() -> usize { $size }
             }
         )+
diff --git a/tests/debugger_visualizer.rs b/tests/debugger_visualizer.rs
new file mode 100644
index 0000000..210f539
--- /dev/null
+++ b/tests/debugger_visualizer.rs
@@ -0,0 +1,68 @@
+use debugger_test::debugger_test;
+use smallvec::{smallvec, SmallVec};
+
+#[inline(never)]
+fn __break() {}
+
+#[debugger_test(
+    debugger = "cdb",
+    commands = r#"
+.nvlist
+dx sv
+
+g
+
+dx sv
+
+g
+
+dx sv
+"#,
+    expected_statements = r#"
+sv               : { len=0x2 } [Type: smallvec::SmallVec<array$<i32,4> >]
+    [<Raw View>]     [Type: smallvec::SmallVec<array$<i32,4> >]
+    [capacity]       : 4
+    [len]            : 0x2 [Type: unsigned __int64]
+    [0]              : 1 [Type: int]
+    [1]              : 2 [Type: int]
+
+sv               : { len=0x5 } [Type: smallvec::SmallVec<array$<i32,4> >]
+    [<Raw View>]     [Type: smallvec::SmallVec<array$<i32,4> >]
+    [capacity]       : 0x8 [Type: unsigned __int64]
+    [len]            : 0x5 [Type: unsigned __int64]
+    [0]              : 5 [Type: int]
+    [1]              : 2 [Type: int]
+    [2]              : 3 [Type: int]
+    [3]              : 4 [Type: int]
+    [4]              : 5 [Type: int]
+
+sv               : { len=0x5 } [Type: smallvec::SmallVec<array$<i32,4> >]
+    [<Raw View>]     [Type: smallvec::SmallVec<array$<i32,4> >]
+    [capacity]       : 0x8 [Type: unsigned __int64]
+    [len]            : 0x5 [Type: unsigned __int64]
+    [0]              : 2 [Type: int]
+    [1]              : 3 [Type: int]
+    [2]              : 4 [Type: int]
+    [3]              : 5 [Type: int]
+    [4]              : 5 [Type: int]
+"#
+)]
+#[inline(never)]
+fn test_debugger_visualizer() {
+    // This SmallVec can hold up to 4 items on the stack:
+    let mut sv: SmallVec<[i32; 4]> = smallvec![1, 2];
+    __break();
+
+    // Overfill the SmallVec to move its contents to the heap
+    for i in 3..6 {
+        sv.push(i);
+    }
+
+    // Update the contents of the first value of the SmallVec.
+    sv[0] = sv[1] + sv[2];
+    __break();
+
+    // Sort the SmallVec in place.
+    sv.sort();
+    __break();
+}