Refused JSON contracts built by reflection and checked all of them in the trimmed build (#1152)

app/Tests/Components/JsonTreeViewTests.cs

@@ -0,0 +1,46 @@
+using System.Text.Json.Nodes;
+
+using AIStudio.Components;
+
+namespace AIStudio.Tests.Components;
+
+/// <summary>
+/// Checks how the tree of a tool result in the chat writes its keys and values.
+/// </summary>
+/// <remarks>
+/// The tree writes each key and each value as JSON. Escaping for a web page, as the default encoder of
+/// System.Text.Json does, would show every umlaut and every quotation mark as a code of six characters,
+/// although Blazor encodes the text for the page anyway. A value parsed from JSON goes through the same
+/// writer as one created in code, so both get checked.
+/// </remarks>
+[TestFixture]
+public sealed class JsonTreeViewTests
+{
+    [TestCase("Größe der Übersicht")]
+    [TestCase("if (a < b && c > d) return 'x' + y;")]
+    [TestCase("日本語のテキスト")]
+    public void ValuesAppearAsWritten(string text)
+    {
+        var parsed = JsonNode.Parse(new JsonObject { ["text_content"] = text }.ToJsonString())!["text_content"];
+        using (Assert.EnterMultipleScope())
+        {
+            Assert.That(JsonTreeView.FormatValue(JsonValue.Create(text)), Is.EqualTo($"\"{text}\""), "A value created in code.");
+            Assert.That(JsonTreeView.FormatValue(parsed), Is.EqualTo($"\"{text}\""), "A value parsed from JSON.");
+        }
+    }
+
+    [TestCase("Größe")]
+    [TestCase("a < b && c > d")]
+    public void KeysAppearAsWritten(string key) => Assert.That(JsonTreeView.FormatKey(key), Is.EqualTo($"\"{key}\""));
+
+    [Test]
+    public void WhatJsonHasToEscapeStaysEscaped()
+    {
+        const string TEXT = "A \"quoted\" line\nand a backslash \\ at its end.";
+        using (Assert.EnterMultipleScope())
+        {
+            Assert.That(JsonNode.Parse(JsonTreeView.FormatValue(JsonValue.Create(TEXT)))?.GetValue<string>(), Is.EqualTo(TEXT), "A value.");
+            Assert.That(JsonNode.Parse(JsonTreeView.FormatKey(TEXT))?.GetValue<string>(), Is.EqualTo(TEXT), "A key.");
+        }
+    }
+}