Ollama improvements (#283)

* Add basic tests
* Add note about input tokens limitation (Fixes #276)

R/provider-ollama.R

@@ -14,6 +14,9 @@
 #'
 #' * Tool calling is not supported with streaming (i.e. when `echo` is
 #'   `"text"` or `"all"`)
+#' * Models can only use 2048 input tokens, and there's no way
+#'   to get them to use more, except by creating a custom model with a
+#'   different default.
 #' * Tool calling generally seems quite weak, at least with the models I have
 #'   tried it with.
 #'
@@ -58,6 +61,14 @@ chat_ollama <- function(system_prompt = NULL,
   )
 }
 
+chat_ollama_test <- function(..., model = "llama3.3") {
+  if (!has_ollama()) {
+    testthat::skip("ollama not found")
+  }
+
+  chat_ollama(..., model = model)
+}
+
 ollama_models <- function(base_url = "http://localhost:11434") {
   req <- request(base_url)
   req <- req_url_path(req, "api/tags")

tests/testthat/test-provider-ollama.R

@@ -0,0 +1,19 @@
+# Getting started --------------------------------------------------------
+
+test_that("can make simple request", {
+  chat <- chat_ollama_test("Be as terse as possible; no punctuation")
+  resp <- chat$chat("What is 1 + 1?", echo = FALSE)
+  expect_match(resp, "2")
+  expect_equal(chat$last_turn()@tokens >= 1, c(TRUE, TRUE))
+})
+
+test_that("can make simple streaming request", {
+  chat <- chat_ollama_test("Be as terse as possible; no punctuation")
+  resp <- coro::collect(chat$stream("What is 1 + 1?"))
+  expect_match(paste0(unlist(resp), collapse = ""), "2")
+})
+
+# Common provider interface -----------------------------------------------
+
+# Currently no other tests because I can't find a model that returns reliable
+# results and is reasonably performant.