Inspector: Expand and show properties in a TreeView

This allows the inspector to show arbitrary json structures.

AK/JsonPath.h

@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) 2020, The SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <AK/Optional.h>
+#include <AK/String.h>
+#include <AK/Types.h>
+#include <AK/Vector.h>
+
+namespace AK {
+
+class JsonPathElement {
+public:
+    enum class Kind {
+        Key,
+        Index,
+        AnyIndex,
+        AnyKey,
+    };
+
+    JsonPathElement(size_t index)
+        : m_kind(Kind::Index)
+        , m_index(index)
+    {
+    }
+
+    JsonPathElement(const StringView& key)
+        : m_kind(Kind::Key)
+        , m_key(key)
+    {
+    }
+
+    Kind kind() const { return m_kind; }
+    const String& key() const
+    {
+        ASSERT(m_kind == Kind::Key);
+        return m_key;
+    }
+
+    size_t index() const
+    {
+        ASSERT(m_kind == Kind::Index);
+        return m_index;
+    }
+
+    String to_string() const
+    {
+        switch (m_kind) {
+        case Kind::Key:
+            return key();
+        case Kind::Index:
+            return String::number(index());
+        default:
+            return "*";
+        }
+    }
+
+    static JsonPathElement any_array_element;
+    static JsonPathElement any_object_element;
+
+    bool operator==(const JsonPathElement& other) const
+    {
+        switch (other.kind()) {
+        case Kind::Key:
+            return (m_kind == Kind::Key && other.key() == key()) || m_kind == Kind::AnyKey;
+        case Kind::Index:
+            return (m_kind == Kind::Index && other.index() == index()) || m_kind == Kind::AnyIndex;
+        case Kind::AnyKey:
+            return m_kind == Kind::Key;
+        case Kind::AnyIndex:
+            return m_kind == Kind::Index;
+        }
+        return false;
+    }
+    bool operator!=(const JsonPathElement& other) const
+    {
+        return !(*this == other);
+    }
+
+private:
+    Kind m_kind;
+    String m_key;
+    size_t m_index { 0 };
+
+    JsonPathElement(Kind kind)
+        : m_kind(kind)
+    {
+    }
+};
+
+class JsonPath : public Vector<JsonPathElement> {
+public:
+    JsonValue resolve(const JsonValue&) const;
+    String to_string() const;
+};
+
+}
+
+using AK::JsonPath;
+using AK::JsonPathElement;