Start refactoring ide_completion tests

crates/ide_completion/src/tests.rs

@@ -0,0 +1,64 @@
+mod item_list;
+
+use expect_test::Expect;
+use stdx::format_to;
+
+use crate::{
+    test_utils::{self, get_all_items, TEST_CONFIG},
+    CompletionConfig, CompletionItem,
+};
+
+fn completion_list(code: &str) -> String {
+    completion_list_with_config(TEST_CONFIG, code)
+}
+
+fn completion_list_with_config(config: CompletionConfig, code: &str) -> String {
+    fn monospace_width(s: &str) -> usize {
+        s.chars().count()
+    }
+
+    let kind_completions: Vec<CompletionItem> = get_all_items(config, code).into_iter().collect();
+    let label_width = kind_completions
+        .iter()
+        .map(|it| monospace_width(it.label()))
+        .max()
+        .unwrap_or_default()
+        .min(16);
+    kind_completions
+        .into_iter()
+        .map(|it| {
+            let tag = it.kind().unwrap().tag();
+            let var_name = format!("{} {}", tag, it.label());
+            let mut buf = var_name;
+            if let Some(detail) = it.detail() {
+                let width = label_width.saturating_sub(monospace_width(it.label()));
+                format_to!(buf, "{:width$} {}", "", detail, width = width);
+            }
+            if it.deprecated() {
+                format_to!(buf, " DEPRECATED");
+            }
+            format_to!(buf, "\n");
+            buf
+        })
+        .collect()
+}
+
+fn check(ra_fixture: &str, expect: Expect) {
+    let actual = completion_list(ra_fixture);
+    expect.assert_eq(&actual)
+}
+
+fn check_no_completion(ra_fixture: &str) {
+    let (db, position) = test_utils::position(ra_fixture);
+
+    assert!(
+        crate::completions(&db, &TEST_CONFIG, position).is_none(),
+        "Completions were generated, but weren't expected"
+    );
+}
+
+#[test]
+fn test_no_completions_required() {
+    cov_mark::check!(no_completion_required);
+    check_no_completion(r#"fn foo() { for i i$0 }"#);
+}