1 files changed, 131 insertions, 0 deletions
diff --git a/expression-test/test_runner_common.cpp b/expression-test/test_runner_common.cpp
new file mode 100644
index 0000000000..745ef9fced
--- /dev/null
+++ b/expression-test/test_runner_common.cpp
@@ -0,0 +1,131 @@
+#include "test_runner_common.hpp"
+
+#include <cmath>
+#include <regex>
+
+using namespace mbgl;
+
+// Strip precision for numbers, so that we can compare evaluated results with fixtures.
+// Copied from JS expression harness.
+Value stripPrecision(const Value& value) {
+    const double decimalSigFigs = 6;
+    if (auto num = numericValue<double>(value)) {
+        if (*num == 0) {
+            return *num;
+        }
+
+        const double multiplier = std::pow(10, std::max(0.0, decimalSigFigs - std::ceil(std::log10(std::fabs(*num)))));
+
+        // We strip precision twice in a row here to avoid cases where
+        // stripping an already stripped number will modify its value
+        // due to bad floating point precision luck
+        // eg `Math.floor(8.16598 * 100000) / 100000` -> 8.16597
+        const double firstStrip = std::floor(*num * multiplier) / multiplier;
+        return std::floor(firstStrip * multiplier) / multiplier;
+    }
+
+    if (value.is<std::vector<Value>>()) {
+        std::vector<Value> stripped;
+        const auto& vec = value.get<std::vector<Value>>();
+        stripped.reserve(vec.size());
+        for (const auto& val : vec) {
+            stripped.emplace_back(stripPrecision(val));
+        }
+        return stripped;
+    } else if (value.is<std::unordered_map<std::string, Value>>()) {
+        std::unordered_map<std::string, Value> stripped;
+        const auto& map = value.get<std::unordered_map<std::string, Value>>();
+        for (const auto& pair : map) {
+            stripped.emplace(pair.first, stripPrecision(pair.second));
+        }
+        return stripped;
+    }
+
+    return value;
+}
+
+std::vector<std::string> tokenize(std::string str) {
+    std::vector<std::string> tokens;
+    std::regex re("\n");
+    std::copy(std::regex_token_iterator<std::string::iterator>(str.begin(), str.end(), re, -1),
+              std::regex_token_iterator<std::string::iterator>(),
+              std::back_inserter(tokens));
+    return tokens;
+}
+
+bool deepEqual(const Value& a, const Value& b) {
+    const auto& anum = numericValue<double>(a);
+    const auto& bnum = numericValue<double>(b);
+    if (anum && bnum) {
+        return stripPrecision(*anum) == stripPrecision(*bnum);
+    }
+
+    if (a.which() != b.which()) {
+        return false;
+    }
+
+    if (a.getArray() && b.getArray()) {
+        const auto& avec = *a.getArray();
+        const auto& bvec = *b.getArray();
+        if (avec.size() != bvec.size()) {
+            return false;
+        }
+        for (std::size_t i = 0; i < avec.size(); ++i) {
+            if (!deepEqual(avec[i], bvec[i])) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    if (a.getObject() && b.getObject()) {
+        const auto& amap = *a.getObject();
+        const auto& bmap = *b.getObject();
+        if (amap.size() != bmap.size()) {
+            return false;
+        }
+        for (const auto& pair : amap) {
+            auto it = bmap.find(pair.first);
+            if (it == bmap.end()) {
+                return false;
+            }
+            if (!deepEqual(pair.second, it->second)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    if (a == b) {
+        return true;
+    }
+
+    if (a.getString() && b.getString()) {
+        const auto& strA = *a.getString();
+        const auto& strB = *b.getString();
+        if (strA == strB) {
+            return true;
+        }
+
+        try {
+            double numA = std::stod(strA);
+            double numB = std::stod(strB);
+            return stripPrecision(numA) == stripPrecision(numB);
+        } catch (...) {
+        }
+    }
+
+    return false;
+}
+
+bool deepEqual(const optional<Value>& a, const optional<Value>& b) {
+    if ((a && !b) || (!a && b)) {
+        return false;
+    }
+
+    if (a && b) {
+        return deepEqual(*a, *b);
+    }
+
+    return true;
+}