Rebuilt how AI Studio knows what a model can do (#960)

app/Tests/Models/Plugins/ModelDeclarationTests.cs

@@ -0,0 +1,226 @@
+using AIStudio.Models;
+using AIStudio.Models.Matching;
+using AIStudio.Models.Plugins;
+using AIStudio.Provider;
+
+using Lua;
+using Lua.Standard;
+
+using Microsoft.Extensions.Logging.Abstractions;
+
+namespace AIStudio.Tests.Models.Plugins;
+
+/// <summary>
+/// Checks what AI Studio makes of a model an organization describes in a plugin of its own.
+/// </summary>
+/// <remarks>
+/// The entries below are written the way they are written in a plugin.lua, and they are read
+/// through a real Lua state rather than through a table put together in C#. What is being checked
+/// is the wire format an administrator types, so anything between their file and the declaration
+/// has to be part of the test.
+/// </remarks>
+[TestFixture]
+public sealed class ModelDeclarationTests
+{
+    private static readonly Guid PLUGIN_ID = new("11111111-1111-1111-1111-111111111111");
+
+    private const string ORIGIN = "Models of a company";
+
+    private const string A_COMPLETE_DECLARATION = """
+                                                  ["PATTERN"] = "acme-assistant",
+                                                  ["MATCH"] = "PREFIX",
+                                                  ["CAPABILITIES"] = { "TEXT_INPUT", "MULTIPLE_IMAGE_INPUT", "TEXT_OUTPUT", "FUNCTION_CALLING", "CHAT_COMPLETION_API" },
+                                                  ["REASONING"] = "ON_BY_DEFAULT",
+                                                  ["KIND"] = "CHAT",
+                                                  ["CONTEXT_WINDOW"] = 131072,
+                                                  ["CONTEXT_WINDOW_RAISABLE_TO"] = 262144,
+                                                  ["TOKENIZER_KIND"] = "HUGGING_FACE",
+                                                  ["TOKENIZER_ID"] = "acme/assistant",
+                                                  ["MAX_IMAGES_PER_MESSAGE"] = 1,
+                                                  ["MAX_IMAGES_PER_REQUEST"] = 8,
+                                                  ["SOURCE_URL"] = "https://intranet.invalid/ai/acme-assistant",
+                                                  ["SOURCE_CHECKED_ON"] = "2026-09-12",
+                                                  ["SOURCE_NOTE"] = "Internal model card: tools, images, 128k context",
+                                                  """;
+
+    private const string THE_LEAST_A_DECLARATION_CAN_SAY = """
+                                                           ["PATTERN"] = "acme-assistant",
+                                                           ["CAPABILITIES"] = { "TEXT_INPUT", "TEXT_OUTPUT", "CHAT_COMPLETION_API" },
+                                                           ["SOURCE_URL"] = "https://intranet.invalid/ai/acme-assistant",
+                                                           ["SOURCE_CHECKED_ON"] = "2026-09-12",
+                                                           """;
+
+    [Test]
+    public async Task ADeclarationIsReadTheWayItWasWritten()
+    {
+        var declaration = await ReadAsync(A_COMPLETE_DECLARATION);
+
+        Assert.That(declaration, Is.Not.Null);
+        Assert.Multiple(() =>
+        {
+            Assert.That(declaration!.Pattern.Text, Is.EqualTo("acme-assistant"));
+            Assert.That(declaration.Pattern.Kind, Is.EqualTo(MatchKind.PREFIX));
+            Assert.That(declaration.Change.Adds, Is.EqualTo(Capability.TEXT_INPUT | Capability.MULTIPLE_IMAGE_INPUT | Capability.TEXT_OUTPUT | Capability.FUNCTION_CALLING | Capability.CHAT_COMPLETION_API));
+            Assert.That(declaration.Change.Reasoning, Is.EqualTo(ReasoningSupport.ON_BY_DEFAULT));
+            Assert.That(declaration.Change.Kind, Is.EqualTo(ModelKind.CHAT));
+            Assert.That(declaration.Change.Context, Is.EqualTo(ContextWindow.Of(131_072, 262_144)));
+            Assert.That(declaration.Change.Tokenizer, Is.EqualTo(new TokenizerRef(TokenizerKind.HUGGING_FACE, "acme/assistant")));
+            Assert.That(declaration.Change.Images, Is.EqualTo(new ImageLimits(1, 8)));
+            Assert.That(declaration.Source.CheckedOn, Is.EqualTo(new DateOnly(2026, 9, 12)));
+            Assert.That(declaration.EnterpriseConfigurationPluginId, Is.EqualTo(PLUGIN_ID));
+        });
+    }
+
+    [Test]
+    public async Task WhatADeclarationLeavesOutIsTheSameAsWhatAFamilyLeavesOut()
+    {
+        var declaration = await ReadAsync(THE_LEAST_A_DECLARATION_CAN_SAY);
+
+        Assert.That(declaration, Is.Not.Null);
+        Assert.Multiple(() =>
+        {
+            Assert.That(declaration!.Pattern.Kind, Is.EqualTo(MatchKind.SEGMENT), "The kind to reach for by default, here as everywhere else.");
+            Assert.That(declaration.Change.Reasoning, Is.EqualTo(ReasoningSupport.NONE));
+            Assert.That(declaration.Change.Kind, Is.EqualTo(ModelKind.CHAT), "A model nobody said anything else about stays visible in the chat lists.");
+            Assert.That(declaration.Change.Context, Is.Null);
+            Assert.That(declaration.Change.Tokenizer, Is.Null);
+            Assert.That(declaration.Change.Images, Is.Null);
+        });
+    }
+
+    [Test]
+    public async Task ADeclarationWithoutCapabilitiesIsRefused()
+    {
+        //
+        // The one thing a declaration cannot leave out. It replaces what AI Studio would otherwise
+        // say about these models, so an entry naming only a context window would take away every
+        // capability the built-in rules knew -- and it would do so silently, because an entry which
+        // matches is an answer.
+        //
+        var declaration = await ReadAsync("""
+                                          ["PATTERN"] = "acme-assistant",
+                                          ["CONTEXT_WINDOW"] = 131072,
+                                          ["SOURCE_URL"] = "https://intranet.invalid/ai/acme-assistant",
+                                          ["SOURCE_CHECKED_ON"] = "2026-09-12",
+                                          """);
+
+        Assert.That(declaration, Is.Null);
+    }
+
+    [TestCase("""["PATTERN"] = "Acme-Assistant",""", TestName = "A pattern in capitals", Description = "Names arrive in lower case, so this could never match.")]
+    [TestCase("""["PATTERN"] = "acme_assistant",""", TestName = "A pattern with an underscore")]
+    [TestCase("""["PATTERN"] = "acme assistant",""", TestName = "A pattern with a space")]
+    [TestCase("""["PATTERN"] = "",""", TestName = "No pattern at all")]
+    public async Task APatternWhichCouldNeverMatchAnythingIsRefused(string pattern)
+    {
+        var declaration = await ReadAsync($$"""
+                                            {{pattern}}
+                                            ["CAPABILITIES"] = { "TEXT_INPUT", "TEXT_OUTPUT" },
+                                            ["SOURCE_URL"] = "https://intranet.invalid/ai/acme-assistant",
+                                            ["SOURCE_CHECKED_ON"] = "2026-09-12",
+                                            """);
+
+        Assert.That(declaration, Is.Null, "A pattern which is not written the way a model name is written is a mistake, not a rule which happens to stay quiet.");
+    }
+
+    [TestCase("ALWAYS_REASONING")]
+    [TestCase("OPTIONAL_REASONING")]
+    [TestCase("REASONING_BY_DEFAULT")]
+    public async Task ReasoningStatedAsACapabilityIsRefusedRatherThanDropped(string reasoningWord)
+    {
+        //
+        // The three words are the vocabulary of the expert settings, where a person answers three
+        // questions with yes and no. Here one key says how a model reasons, and the three of them
+        // together can state answers no model can give. A profile drops them anyway, so accepting
+        // them would mean an administrator wrote something that never took effect.
+        //
+        var declaration = await ReadAsync($$"""
+                                            ["PATTERN"] = "acme-assistant",
+                                            ["CAPABILITIES"] = { "TEXT_INPUT", "TEXT_OUTPUT", "{{reasoningWord}}" },
+                                            ["SOURCE_URL"] = "https://intranet.invalid/ai/acme-assistant",
+                                            ["SOURCE_CHECKED_ON"] = "2026-09-12",
+                                            """);
+
+        Assert.That(declaration, Is.Null);
+    }
+
+    [TestCase("""["SOURCE_CHECKED_ON"] = "2026-09-12",""", TestName = "A page nobody named")]
+    [TestCase("""["SOURCE_URL"] = "https://intranet.invalid/ai",""", TestName = "A day nobody named")]
+    [TestCase("""["SOURCE_URL"] = "https://intranet.invalid/ai", ["SOURCE_CHECKED_ON"] = "12.09.2026",""", TestName = "A day written another way")]
+    public async Task ADeclarationHasToSayWhereItWasReadAndWhen(string source)
+    {
+        //
+        // The compiler asks a family in the source for this, and an organization's declaration
+        // outlives whoever wrote it just the same. Naming the page and the day is what lets the next
+        // administrator find out in a minute whether it still holds.
+        //
+        var declaration = await ReadAsync($$"""
+                                            ["PATTERN"] = "acme-assistant",
+                                            ["CAPABILITIES"] = { "TEXT_INPUT", "TEXT_OUTPUT" },
+                                            {{source}}
+                                            """);
+
+        Assert.That(declaration, Is.Null);
+    }
+
+    [TestCase("""["TOKENIZER_KIND"] = "HUGGING_FACE",""", TestName = "A tokenizer kind without an ID")]
+    [TestCase("""["TOKENIZER_ID"] = "acme/assistant",""", TestName = "A tokenizer ID without a kind")]
+    [TestCase("""["CONTEXT_WINDOW_RAISABLE_TO"] = 262144,""", TestName = "A ceiling without a window")]
+    [TestCase("""["CONTEXT_WINDOW"] = 262144, ["CONTEXT_WINDOW_RAISABLE_TO"] = 131072,""", TestName = "A ceiling below the window")]
+    [TestCase("""["CONTEXT_WINDOW"] = 0,""", TestName = "A window of no tokens")]
+    [TestCase("""["MAX_IMAGES_PER_REQUEST"] = -1,""", TestName = "Fewer than no images")]
+    [TestCase("""["KIND"] = "SOMETHING_ELSE",""", TestName = "A kind of model nobody knows")]
+    [TestCase("""["MATCH"] = "REGEX",""", TestName = "A way of matching which does not exist")]
+    [TestCase("""["ONLY_ON"] = "ACME_CLOUD",""", TestName = "A provider which does not exist")]
+    public async Task AnEntryWhichSaysSomethingUnreadableIsRefusedAsAWhole(string addition)
+    {
+        //
+        // Never read in part: a declaration is one statement, and half of one would answer for the
+        // models it matches just as firmly as a complete one, with the unreadable half missing and
+        // nothing on screen saying so.
+        //
+        var declaration = await ReadAsync($"""
+                                           {THE_LEAST_A_DECLARATION_CAN_SAY}
+                                           {addition}
+                                           """);
+
+        Assert.That(declaration, Is.Null);
+    }
+
+    [Test]
+    public async Task TwoDeclarationsCollideExactlyWhenTheyClaimTheSameNames()
+    {
+        //
+        // What identifies a declaration is its pattern, because that is what a collision is here.
+        // Two of them claiming the same names would both enter the index and tie there, and a tie
+        // is something only a person can settle. Two about different names never meet.
+        //
+        var declaration = await ReadAsync(A_COMPLETE_DECLARATION);
+        var theSameNames = await ReadAsync(A_COMPLETE_DECLARATION.Replace("""["CONTEXT_WINDOW"] = 131072,""", """["CONTEXT_WINDOW"] = 65536,""", StringComparison.Ordinal));
+        var otherNames = await ReadAsync(A_COMPLETE_DECLARATION.Replace("""["MATCH"] = "PREFIX",""", """["MATCH"] = "SEGMENT",""", StringComparison.Ordinal));
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(theSameNames?.Id, Is.EqualTo(declaration?.Id), "The same pattern, so one of the two has to win.");
+            Assert.That(otherNames?.Id, Is.Not.EqualTo(declaration?.Id), "Bound to the name differently, so they claim different sets of names.");
+        });
+    }
+
+    private static async Task<ModelDeclaration?> ReadAsync(string entry)
+    {
+        var state = LuaState.Create();
+        state.OpenBasicLibrary();
+        state.OpenTableLibrary();
+
+        await state.DoStringAsync($$"""
+                                    MODEL = {
+                                        {{entry}}
+                                    }
+                                    """);
+
+        if (!state.Environment["MODEL"].TryRead<LuaTable>(out var table))
+            throw new InvalidOperationException("The entry of this test is not a Lua table.");
+
+        return ModelDeclaration.TryParse(1, table, PLUGIN_ID, ORIGIN, NullLogger.Instance, out var declaration) ? declaration : null;
+    }
+}