1 files changed, 115 insertions, 0 deletions
diff --git a/test/example/space.cpp b/test/example/space.cpp
new file mode 100644
index 000000000..33256eedf
--- /dev/null
+++ b/test/example/space.cpp
@@ -0,0 +1,115 @@
+#include <cassert>
+#include <iostream>
+
+#include <support/space.h>
+
+using namespace wasm;
+
+using Span = DisjointSpans::Span;
+
+int main() {
+  // No spans
+  {
+    DisjointSpans root;
+    // Nothing in root
+    assert(!root.checkOverlap(Span{0, 100}));
+  }
+  // One span
+  {
+    DisjointSpans root;
+    root.add(Span{0, 100});
+    // It is there
+    assert(root.checkOverlap(Span{0, 100}));
+  }
+  {
+    DisjointSpans root;
+    root.add(Span{40, 60});
+    // Exact match
+    assert(root.checkOverlap(Span{40, 60}));
+    // No overlap
+    assert(!root.checkOverlap(Span{20, 30}));
+    // Touching, but no overlap
+    assert(!root.checkOverlap(Span{20, 40}));
+    // Overlap
+    assert(root.checkOverlap(Span{20, 41}));
+    assert(root.checkOverlap(Span{40, 41}));
+    // Internal
+    assert(root.checkOverlap(Span{45, 50}));
+    // Touches other side
+    assert(root.checkOverlap(Span{45, 60}));
+    // Overlaps on other side
+    assert(root.checkOverlap(Span{45, 70}));
+    // Just inside.
+    assert(root.checkOverlap(Span{59, 60}));
+    // Just outside
+    assert(!root.checkOverlap(Span{60, 61}));
+    // Totally outside
+    assert(!root.checkOverlap(Span{70, 80}));
+  }
+  // Two spans, different subtrees
+  {
+    DisjointSpans root;
+    root.add(Span{30, 40});
+    root.add(Span{60, 70});
+    assert(!root.checkOverlap(Span{10, 20}));
+    assert(!root.checkOverlap(Span{10, 30}));
+    assert(root.checkOverlap(Span{10, 40}));
+    assert(root.checkOverlap(Span{35, 40}));
+    assert(!root.checkOverlap(Span{40, 60}));
+    assert(!root.checkOverlap(Span{45, 55}));
+    assert(root.checkOverlap(Span{50, 61}));
+    assert(root.checkOverlap(Span{50, 100}));
+    assert(root.checkOverlap(Span{60, 70}));
+    assert(root.checkOverlap(Span{60, 61}));
+    assert(!root.checkOverlap(Span{70, 80}));
+    assert(!root.checkOverlap(Span{70, 100}));
+  }
+  // Two spans, same subtree
+  {
+    DisjointSpans root;
+    root.add(Span{30, 40});
+    root.add(Span{40, 45});
+    assert(!root.checkOverlap(Span{10, 20}));
+    assert(!root.checkOverlap(Span{10, 30}));
+    assert(root.checkOverlap(Span{10, 40}));
+    assert(root.checkOverlap(Span{35, 40}));
+    assert(root.checkOverlap(Span{40, 41}));
+    assert(root.checkOverlap(Span{35, 45}));
+    assert(!root.checkOverlap(Span{45, 100}));
+  }
+  // "Pixels"
+  {
+    const int N = 40;
+    for (int i = 0; i < N; i++) {
+      DisjointSpans root;
+      for (int j = 0; j < N; j++) {
+        // add all pixels but the i-th
+        if (j != i) {
+          root.add(Span{j, j + 1});
+        }
+      }
+      for (int j = 0; j < N; j++) {
+        if (j != i) {
+          assert(root.checkOverlap(Span{j, j + 1}));
+        } else {
+          assert(!root.checkOverlap(Span{j, j + 1}));
+        }
+      }
+      assert(root.checkOverlap(Span{10, N + 10}));
+      assert(!root.checkOverlap(Span{N + 10, N + 20}));
+    }
+  }
+  // Large numbers.
+  {
+    DisjointSpans root;
+    assert(!root.checkOverlap(Span{2948, 2949}));
+    root.add(Span{2948, 2949});
+    assert(root.checkOverlap(Span{2948, 2949}));
+    assert(root.checkOverlap(Span{2940, 2949}));
+    assert(root.checkOverlap(Span{2948, 2959}));
+    assert(root.checkOverlap(Span{0, 18766}));
+    assert(!root.checkOverlap(Span{2000, 2001}));
+    assert(!root.checkOverlap(Span{3000, 3001}));
+  }
+  std::cout << "success.\n";
+}