Added mailboxes as local data sources (#1022)

app/Tests/Tools/ToolCalling/ToolArgumentReaderTests.cs

@@ -1,3 +1,4 @@
+using System.Globalization;
 using System.Text.Json;
 
 using AIStudio.Tools.ToolCallingSystem;
@@ -11,7 +12,8 @@ namespace AIStudio.Tests.Tools.ToolCalling;
 /// The web search tests cover strings, positive integers, and a single choice through the
 /// arguments of that tool. What is left are a required string which arrives empty and a list of
 /// choices, which the web search does not have: a data source a model names has to be one the
-/// tool offered, and the refusal has to say which ones those are.
+/// tool offered, and the refusal has to say which ones those are. The mail tools add booleans,
+/// dates, and single lines which go into a search.
 /// </remarks>
 [TestFixture]
 public sealed class ToolArgumentReaderTests
@@ -88,8 +90,76 @@ public sealed class ToolArgumentReaderTests
         Assert.That(message, Does.Contain($"but one was \"{id}\"."), "Data sources are named by their GUIDs; a shortened one would leave the model guessing.");
     }
 
+    [TestCase("true", true)]
+    [TestCase("false", false)]
+    public void ABooleanComesThroughAsItIs(string value, bool expected)
+    {
+        Assert.That(ToolArgumentReader.ReadOptionalBoolean(Arguments($$"""{"is_unread":{{value}}}"""), "is_unread", WHEN_LEFT_OUT), Is.EqualTo(expected));
+    }
+
+    [TestCase("\"true\"")]
+    [TestCase("1")]
+    [TestCase("\"yes\"")]
+    public void AnythingButABooleanIsRefused(string value)
+    {
+        var message = Refusal(() => ToolArgumentReader.ReadOptionalBoolean(Arguments($$"""{"is_unread":{{value}}}"""), "is_unread", WHEN_LEFT_OUT));
+
+        Assert.That(message, Does.Contain("'is_unread' must be true or false").And.Contain($"Leave it out {WHEN_LEFT_OUT}."));
+    }
+
+    [TestCase("2026-09-01", "2026-09-01T00:00:00+02:00")]
+    [TestCase("2026-09-01T14:30", "2026-09-01T14:30:00+02:00")]
+    [TestCase("2026-09-01T14:30:15", "2026-09-01T14:30:15+02:00")]
+    [TestCase("2026-09-01T14:30:00+05:00", "2026-09-01T14:30:00+05:00")]
+    [TestCase("2026-09-01T14:30:00Z", "2026-09-01T14:30:00+00:00")]
+    public void ADateWithoutAnOffsetIsReadInTheTimeZoneOfTheUser(string value, string expected)
+    {
+        var pointInTime = ToolArgumentReader.ReadOptionalDateTime(Arguments($$"""{"after":"{{value}}"}"""), "after", UserTimeZone(), WHEN_LEFT_OUT);
+        var expectedPointInTime = DateTimeOffset.Parse(expected, CultureInfo.InvariantCulture);
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(pointInTime, Is.EqualTo(expectedPointInTime));
+            Assert.That(pointInTime?.Offset, Is.EqualTo(expectedPointInTime.Offset), "The same instant with another offset would hide which zone was assumed.");
+        });
+    }
+
+    [TestCase("\"yesterday\"")]
+    [TestCase("\"01.09.2026\"")]
+    [TestCase("\"2026-9-1\"")]
+    [TestCase("\"2026-02-30\"")]
+    [TestCase("20260901")]
+    public void ADateInAnotherFormIsRefused(string value)
+    {
+        var message = Refusal(() => ToolArgumentReader.ReadOptionalDateTime(Arguments($$"""{"after":{{value}}}"""), "after", UserTimeZone(), WHEN_LEFT_OUT));
+
+        Assert.That(message, Does.Contain("'after' must be a date such as 2026-09-01").And.Contain($"Leave it out {WHEN_LEFT_OUT}."));
+    }
+
+    [Test]
+    public void ALineComesThroughTrimmed()
+    {
+        Assert.That(ToolArgumentReader.ReadOptionalLine(Arguments("""{"from":"  alice@example.org "}"""), "from", 20, WHEN_LEFT_OUT), Is.EqualTo("alice@example.org"));
+    }
+
+    [TestCase("\"\"", "must not be empty")]
+    [TestCase("\"   \"", "must not be empty")]
+    [TestCase("\"alice@example.org and bob@example.org\"", "must be at most 20 characters long, but had 37")]
+    [TestCase("\"alice\\nbob\"", "must not contain control characters")]
+    public void AnEmptyOrLongOrBrokenLineIsRefused(string value, string expectedReason)
+    {
+        var message = Refusal(() => ToolArgumentReader.ReadOptionalLine(Arguments($$"""{"from":{{value}}}"""), "from", 20, WHEN_LEFT_OUT));
+
+        Assert.That(message, Does.Contain($"'from' {expectedReason}").And.Contain($"Leave it out {WHEN_LEFT_OUT}."), "In a search, an empty line would match everything. Whatever was wrong, leaving the argument out is always a way out.");
+    }
+
     private static JsonElement Arguments(string json) => JsonSerializer.Deserialize<JsonElement>(json);
 
+    /// <summary>
+    /// A time zone two hours ahead of UTC, all year round, so that no test depends on the computer or on daylight saving time.
+    /// </summary>
+    private static TimeZoneInfo UserTimeZone() => TimeZoneInfo.CreateCustomTimeZone("AI Studio test zone", TimeSpan.FromHours(2), "AI Studio test zone", "AI Studio test zone");
+
     /// <summary>
     /// Runs a reader which has to refuse its argument and returns what it said.
     /// </summary>