[clang] Introduce paged vector (PR #66430)

[Jakub Kuderski via cfe-commits]

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@@ -0,0 +1,92 @@
+//===- llvm/unittest/ADT/PagedVectorTest.cpp ------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// PagedVector unit tests.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/PagedVector.h"
+#include "gtest/gtest.h"
+
+namespace llvm {
+TEST(PagedVectorTest, FunctionalityTest) {
+  PagedVector<int, 10> V;
+  EXPECT_EQ(V.empty(), true);
+
+  // Next ten numbers are 10..19
+  V.expand(2);
+  EXPECT_EQ(V.empty(), false);
+  V.expand(10);
+  V.expand(20);
+  V.expand(30);
+  EXPECT_EQ(V.materialised().size(), 0ULL);
+
+  EXPECT_EQ(V.size(), 30ULL);
+  for (int I = 0; I < 10; ++I) {
+    V[I] = I;
+  }
+  for (int I = 0; I < 10; ++I) {
+    EXPECT_EQ(V[I], I);
+  }
+  EXPECT_EQ(V.materialised().size(), 10ULL);
+  for (int I = 20; I < 30; ++I) {
+    V[I] = I;
+  }
+  for (int I = 20; I < 30; ++I) {
+    EXPECT_EQ(V[I], I);
+  }
+  EXPECT_EQ(V.materialised().size(), 20ULL);
+
+  for (int I = 10; I < 20; ++I) {
+    V[I] = I;
+  }
+  for (int I = 10; I < 20; ++I) {
+    EXPECT_EQ(V[I], I);
+  }
+  EXPECT_EQ(V.materialised().size(), 30ULL);
+  V.expand(35);
+  EXPECT_EQ(V.materialised().size(), 30ULL);
+  for (int I = 30; I < 35; ++I) {
+    V[I] = I;
+  }
+  EXPECT_EQ(V.materialised().size(), 40ULL);
+  EXPECT_EQ(V.size(), 35ULL);
+  EXPECT_EQ(V.capacity(), 40ULL);
+  V.expand(37);
+  for (int I = 30; I < 37; ++I) {
+    V[I] = I;
+  }
+  EXPECT_EQ(V.size(), 37ULL);
+  EXPECT_EQ(V.capacity(), 40ULL);
+  for (int I = 0; I < 37; ++I) {
+    EXPECT_EQ(V[I], I);
+  }
+
+  V.expand(41);
+  V[40] = 40;
+  EXPECT_EQ(V.size(), 41ULL);
+  EXPECT_EQ(V.capacity(), 50ULL);
+  for (int I = 0; I < 36; ++I) {
+    EXPECT_EQ(V[I], I);
+    EXPECT_EQ(V.at(I), I);
+  }
+  for (int I = 37; I < 40; ++I) {
+    EXPECT_EQ(V[I], 0);
+    EXPECT_EQ(V.at(I), 0);
+  }
+  V.expand(50);
----------------
kuhar wrote:

Could you split this into multiple smaller tests? I find it difficult to tell what each block of code is trying to test.

https://github.com/llvm/llvm-project/pull/66430