diff --git a/Cargo.lock b/Cargo.lock
index 4040cd3..64071e0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -137,6 +137,15 @@ version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
+[[package]]
+name = "bstr"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba3569f383e8f1598449f1a423e72e99569137b47740b1da11ef19af3d5c3223"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "byteorder"
 version = "1.4.3"
@@ -438,6 +447,19 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
 
+[[package]]
+name = "globset"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "10463d9ff00a2a068db14231982f5132edebad0d7660cd956a1c30292dbcbfbd"
+dependencies = [
+ "aho-corasick",
+ "bstr",
+ "fnv",
+ "log",
+ "regex",
+]
+
 [[package]]
 name = "h2"
 version = "0.3.13"
@@ -790,6 +812,7 @@ dependencies = [
  "cfgrammar",
  "console-subscriber",
  "glob",
+ "globset",
  "log",
  "lrlex",
  "lrpar",
@@ -805,6 +828,7 @@ dependencies = [
  "tokio",
  "tokio-stream",
  "toml",
+ "toml-spanned-value",
  "tower-lsp",
 ]
 
@@ -1404,6 +1428,16 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "toml-spanned-value"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a1991312b7a0e66feb44bc16d97861c20ca476a3c6960bf888d25030dcf4d9f"
+dependencies = [
+ "serde",
+ "toml",
+]
+
 [[package]]
 name = "tonic"
 version = "0.7.2"
diff --git a/server/Cargo.toml b/server/Cargo.toml
index f9e3216..7653251 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -24,6 +24,8 @@ tokio-stream = "0.1.8"
 ropey = "1.4.1"
 railroad = "0.1.1"
 glob = "0.3.0"
+toml-spanned-value = "0.1.0"
+globset = "0.4.8"
 
 [dependencies.console-subscriber]
 version = "0.1.4"
diff --git a/server/src/main.rs b/server/src/main.rs
index 211c805..5555237 100644
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -3,7 +3,6 @@ mod peek_channel;
 
 use cfgrammar::yacc;
 use parse_thread::{ParseThread, ParserMsg};
-use serde;
 use tower_lsp::jsonrpc;
 use tower_lsp::lsp_types as lsp;
 
@@ -152,6 +151,7 @@ async fn process_parser_messages(
                         })
                         .await;
                 }
+                // This should probably be named something like ProgressInterrupt
                 ParserMsg::ProgressCancel(token) => {
                     let token = lsp::NumberOrString::Number(token);
 
@@ -186,32 +186,53 @@ struct State {
     warned_needs_restart: bool,
 }
 
+#[derive(serde::Deserialize, serde::Serialize, Debug)]
+struct TomlTest(Vec<toml::Spanned<String>>);
+
 impl State {
     fn affected_parsers(&self, path: &std::path::Path, ids: &mut Vec<usize>) {
         if let Some(extension) = path.extension() {
-            let id = self.extensions.get(extension).map(ParserInfo::id);
-            // A couple of corner cases here:
-            //
-            // * The kind of case where you have foo.l and bar.y/baz.y using the same lexer.
-            //    -- We should probably allow this case where editing a single file updates multiple parsers.
-            // * The kind of case where you have a yacc.y for the extension .y, so both the extension
-            //   and the parse_info have the same id.
-            //    -- We don't want to run the same parser multiple times: remove duplicates.
-            // In the general case, where you either change a .l, .y, or a file of the parsers extension
-            // this will be a vec of one element.
-            if let Some(id) = id {
-                ids.push(id);
-            }
+            // FIXME should be a globset of toml tests?
+            if extension == "toml" {
+                let stem = path.file_stem();
+                if let Some(stem) = stem {
+                    let stem = std::path::PathBuf::from(stem);
+                    let extension = stem.extension();
+                    if let Some(extension) = extension {
+                        let id = self.extensions.get(extension).map(ParserInfo::id);
+                        if let Some(id) = id {
+                            ids.push(id);
+                        }
+                    }
+                }
+            } else {
+                let id = self.extensions.get(extension).map(ParserInfo::id);
+
+                // A couple of corner cases here:
+                //
+                // * The kind of case where you have foo.l and bar.y/baz.y using the same lexer.
+                //    -- We should probably allow this case where editing a single file updates multiple parsers.
+                // * The kind of case where you have a yacc.y for the extension .y, so both the extension
+                //   and the parse_info have the same id.
+                //    -- We don't want to run the same parser multiple times: remove duplicates.
+                // In the general case, where you either change a .l, .y, or a file of the parsers extension
+                // this will be a vec of one element.
+                if let Some(id) = id {
+                    ids.push(id);
+                }
 
-            ids.extend(
-                self.extensions
-                    .values()
-                    .filter(|parser_info| path == parser_info.l_path || path == parser_info.y_path)
-                    .map(ParserInfo::id),
-            );
+                ids.extend(
+                    self.extensions
+                        .values()
+                        .filter(|parser_info| {
+                            path == parser_info.l_path || path == parser_info.y_path
+                        })
+                        .map(ParserInfo::id),
+                );
 
-            ids.sort_unstable();
-            ids.dedup();
+                ids.sort_unstable();
+                ids.dedup();
+            }
         }
     }
 
@@ -223,8 +244,7 @@ impl State {
     }
 
     fn parser_for(&self, path: &std::path::Path) -> Option<&ParserInfo> {
-        path.extension()
-            .map_or(None, |ext| self.extensions.get(ext))
+        path.extension().and_then(|ext| self.extensions.get(ext))
     }
 }
 
@@ -397,8 +417,42 @@ impl tower_lsp::LanguageServer for Backend {
         let mut state = self.state.lock().await;
         let state = state.deref_mut();
         let mut globs: Vec<lsp::Registration> = Vec::new();
+
         if state.client_monitor {
             for WorkspaceCfg { workspace, .. } in state.toml.values() {
+                for test in &workspace.tests {
+                    if let nimbleparse_toml::TestKind::Toml {
+                        parser_extension: _parser_extension,
+                        toml_test_extension,
+                    } = test.kind.clone().into_inner()
+                    {
+                        self.client
+                            .log_message(
+                                lsp::MessageType::LOG,
+                                format!("registering toml test: {:?}", &test),
+                            )
+                            .await;
+
+                        let mut reg = serde_json::Map::new();
+                        reg.insert(
+                            "globPattern".to_string(),
+                            serde_json::value::Value::String(format!("*/{}", toml_test_extension)),
+                        );
+                        let mut watchers = serde_json::Map::new();
+                        watchers.insert(
+                            "watchers".to_string(),
+                            serde_json::value::Value::Array(vec![
+                                serde_json::value::Value::Object(reg),
+                            ]),
+                        );
+                        globs.push(lsp::Registration {
+                            id: "1".to_string(),
+                            method: "workspace/didChangeWatchedFiles".to_string(),
+                            register_options: Some(serde_json::value::Value::Object(watchers)),
+                        });
+                    }
+                }
+
                 for parser in workspace.parsers.get_ref() {
                     let glob = format!("**/*{}", parser.extension.get_ref());
                     let mut reg = serde_json::Map::new();
@@ -532,6 +586,7 @@ impl tower_lsp::LanguageServer for Backend {
         let url = params.text_document.uri.clone();
         let path = url.to_file_path();
         let nimbleparse_toml = std::ffi::OsStr::new("nimbleparse.toml");
+
         match path {
             Ok(path) if Some(nimbleparse_toml) == path.file_name() => {
                 if !state.warned_needs_restart {
@@ -594,6 +649,7 @@ impl tower_lsp::LanguageServer for Backend {
         let mut state = self.state.lock().await;
         let url = params.text_document.uri.clone();
         let path = url.to_file_path();
+
         match path {
             Ok(path) => {
                 let mut ids = vec![];
diff --git a/server/src/parse_thread.rs b/server/src/parse_thread.rs
index b2e2a62..f6285dd 100644
--- a/server/src/parse_thread.rs
+++ b/server/src/parse_thread.rs
@@ -236,26 +236,23 @@ impl ParseThread {
 
         change_set.clear();
 
-        for test_dir in self.test_dirs() {
-            let nimbleparse_toml::TestKind::Dir(glob) = test_dir.kind.clone().into_inner();
-            {
+        for test in self.tests().iter().cloned() {
+            if let nimbleparse_toml::TestKind::Dir(glob) = test.kind.into_inner() {
                 let abs_glob_as_path = self.workspace_path.join(glob);
                 let glob_str = abs_glob_as_path.to_str().unwrap();
                 let paths = glob::glob(glob_str);
                 if let Ok(paths) = paths {
-                    for test_dir_path in paths {
-                        if let Ok(test_dir_path) = test_dir_path {
-                            let files_of_extension = files.iter().filter(|(test_path, _file)| {
-                                test_path.extension() == Some(&self.parser_info.extension)
-                                    && test_path.parent()
-                                        == Some(&self.subdir_path(test_dir_path.as_path()))
+                    for test_dir_path in paths.flatten() {
+                        let files_of_extension = files.iter().filter(|(test_path, _file)| {
+                            test_path.extension() == Some(&self.parser_info.extension)
+                                && test_path.parent()
+                                    == Some(&self.subdir_path(test_dir_path.as_path()))
+                        });
+                        for (path, _file) in files_of_extension {
+                            change_set.insert(TestReparse {
+                                path: path.clone(),
+                                pass: test.pass,
                             });
-                            for (path, _file) in files_of_extension {
-                                change_set.insert(TestReparse {
-                                    path: path.clone(),
-                                    pass: test_dir.pass,
-                                });
-                            }
                         }
                     }
                 }
@@ -359,7 +356,7 @@ impl ParseThread {
             self.output
                 .send(ParserMsg::Info(format!(
                     "diagnostics {} {} {:?}",
-                    url.clone(),
+                    url,
                     diags.len(),
                     file.version
                 )))
@@ -375,7 +372,7 @@ impl ParseThread {
         }
     }
 
-    pub fn test_dirs(&self) -> &[nimbleparse_toml::TestDir] {
+    pub fn tests(&self) -> &[nimbleparse_toml::Test] {
         self.workspace_cfg.workspace.tests.as_slice()
     }
 
@@ -401,20 +398,48 @@ impl ParseThread {
                 std::collections::HashMap::new();
             let mut change_set: std::collections::HashSet<TestReparse> =
                 std::collections::HashSet::new();
+            let mut gb = globset::GlobSetBuilder::new();
+            if let Some(extension) = self.parser_info.extension.to_str() {
+                let glob = globset::Glob::new(&format!("*.{}", extension));
+                if let Ok(glob) = glob {
+                    gb.add(glob);
+                }
+            }
 
-            // Read in all the test dir files...
-            for nimbleparse_toml::TestDir { kind, .. } in self.test_dirs() {
-                let nimbleparse_toml::TestKind::Dir(glob) = kind.clone().into_inner();
+            for nimbleparse_toml::Test { kind, .. } in self.tests() {
+                if let nimbleparse_toml::TestKind::Toml {
+                    parser_extension,
+                    toml_test_extension,
+                } = kind.clone().into_inner()
                 {
+                    let parser_extension = parser_extension
+                        .strip_prefix('.')
+                        .unwrap_or(&parser_extension);
+                    if parser_extension == self.parser_info.extension {
+                        let x = toml_test_extension
+                            .strip_prefix('.')
+                            .unwrap_or(&toml_test_extension);
+                        let glob = globset::Glob::new(&format!("*.{}", x));
+                        if let Ok(glob) = glob {
+                            gb.add(glob);
+                        }
+                    }
+                }
+            }
+
+            let extensions = gb.build().unwrap();
+            // Read in all the test dir files...
+            for nimbleparse_toml::Test { kind, .. } in self.tests() {
+                if let nimbleparse_toml::TestKind::Dir(glob) = kind.clone().into_inner() {
                     let glob_path = self.workspace_path.join(glob);
                     let glob_str = glob_path.to_str().unwrap();
-                    for dirs in glob::glob(glob_str) {
-                        for dir in dirs {
-                            if let Ok(dir) = dir {
-                                let dir_read = std::fs::read_dir(dir);
-                                if let Ok(dir_read) = dir_read {
-                                    dir_read.for_each(|file| {
-                                        if let Ok(file) = file {
+                    if let Ok(dirs) = glob::glob(glob_str) {
+                        for dir in dirs.flatten() {
+                            let dir_read = std::fs::read_dir(dir);
+                            if let Ok(dir_read) = dir_read {
+                                dir_read.for_each(|file| {
+                                    if let Ok(file) = file {
+                                        if extensions.is_match(file.path()) {
                                             let contents = std::fs::read_to_string(file.path());
                                             if let Ok(contents) = contents {
                                                 let contents = rope::Rope::from(contents);
@@ -427,8 +452,8 @@ impl ParseThread {
                                                 );
                                             }
                                         }
-                                    });
-                                }
+                                    }
+                                });
                             }
                         }
                     }
@@ -515,17 +540,21 @@ impl ParseThread {
                                     }
                                 } else {
                                     let parent = path.parent();
-                                    let test_dir = self.test_dirs().iter().find(|test_dir| {
-                                        let nimbleparse_toml::TestKind::Dir(glob) =
-                                            test_dir.kind.clone().into_inner();
+                                    let test_dir = self.tests().iter().find(|test_dir| {
+                                        if let nimbleparse_toml::TestKind::Dir(glob) =
+                                            test_dir.kind.clone().into_inner()
                                         {
                                             let glob_path = self.workspace_path.join(glob);
                                             let pattern =
                                                 glob::Pattern::new(glob_path.to_str().unwrap())
                                                     .unwrap();
                                             pattern.matches_path(parent.unwrap())
+                                                && extensions.is_match(path.clone())
+                                        } else {
+                                            false
                                         }
                                     });
+
                                     if let Some(test_dir) = test_dir {
                                         let change = TestReparse {
                                             path: path.to_path_buf(),
@@ -591,18 +620,21 @@ impl ParseThread {
                                         }
                                     } else {
                                         let parent = path.parent();
-                                        let test_dir = self.test_dirs().iter().find(|test_dir| {
-                                            let nimbleparse_toml::TestKind::Dir(glob) =
-                                                test_dir.kind.clone().into_inner();
-                                            {
-                                                let glob_path = self.workspace_path.join(glob);
-                                                let pattern =
-                                                    glob::Pattern::new(glob_path.to_str().unwrap())
-                                                        .unwrap();
-                                                pattern.matches_path(parent.unwrap())
+                                        let test = self.tests().iter().find(|test| {
+                                            match test.kind.clone().into_inner() {
+                                                nimbleparse_toml::TestKind::Dir(glob) => {
+                                                    let glob_path = self.workspace_path.join(glob);
+                                                    let pattern = glob::Pattern::new(
+                                                        glob_path.to_str().unwrap(),
+                                                    )
+                                                    .unwrap();
+                                                    pattern.matches_path(parent.unwrap())
+                                                        && extensions.is_match(&path)
+                                                }
+                                                nimbleparse_toml::TestKind::Toml { .. } => false,
                                             }
                                         });
-                                        if let Some(test_dir) = test_dir {
+                                        if let Some(test_dir) = test {
                                             let change = TestReparse {
                                                 path: path.to_path_buf(),
                                                 pass: test_dir.pass,
@@ -666,7 +698,7 @@ impl ParseThread {
                                     let mut choice = railroad::Choice::new(vec![]);
                                     for symbols in prod_syms {
                                         let mut a_seq = railroad::Sequence::new(vec![]);
-                                        if symbols.len() > 0 {
+                                        if symbols.is_empty() {
                                             for symbol in symbols {
                                                 match symbol {
                                                     cfgrammar::Symbol::Rule(prod_ridx)
@@ -751,7 +783,7 @@ impl ParseThread {
                                     let lexer = lexerdef.lexer(&input);
                                     let generic_tree_text = if let Some(pb) = &pb {
                                         let (tree, _) = pb.parse_generictree(&lexer);
-                                        tree.map_or(None, |tree| Some(tree.pp(&grm, &input)))
+                                        tree.map(|tree| tree.pp(&grm, &input))
                                     } else {
                                         None
                                     };
@@ -789,21 +821,25 @@ impl ParseThread {
                             let TestReparse { path, pass } = &reparse;
                             let file = files.get(path);
                             if let Some(file) = file {
-                                let message: String = format!(
-                                    "{i}/{n} {}",
-                                    path.strip_prefix(&self.workspace_path).unwrap().display()
-                                );
-                                self.parse_file(file, path, lexerdef, pb, *pass);
-                                let pcnt = ((i as f32 / n as f32) * 100.0).ceil();
-                                self.output
-                                    .send(ParserMsg::Info(format!(
-                                        "parsed {} {} {} {}",
-                                        token, message, pcnt as u32, pass
-                                    )))
-                                    .unwrap();
-                                self.output
-                                    .send(ParserMsg::ProgressStep(token, message, pcnt as u32))
-                                    .unwrap();
+                                if path.extension() == Some(&self.parser_info.extension) {
+                                    let message: String = format!(
+                                        "{i}/{n} {}",
+                                        path.strip_prefix(&self.workspace_path).unwrap().display()
+                                    );
+                                    self.parse_file(file, path, lexerdef, pb, *pass);
+                                    let pcnt = ((i as f32 / n as f32) * 100.0).ceil();
+                                    self.output
+                                        .send(ParserMsg::Info(format!(
+                                            "parsed {} {} {} {}",
+                                            token, message, pcnt as u32, pass
+                                        )))
+                                        .unwrap();
+                                    self.output
+                                        .send(ParserMsg::ProgressStep(token, message, pcnt as u32))
+                                        .unwrap();
+                                } else {
+                                    // TODO Must be a toml test...
+                                }
                                 change_set.remove(&reparse);
                                 //std::thread::sleep(std::time::Duration::from_millis(500));
                             } else {
diff --git a/toml/src/lib.rs b/toml/src/lib.rs
index ed565ee..134d279 100644
--- a/toml/src/lib.rs
+++ b/toml/src/lib.rs
@@ -5,7 +5,7 @@ use std::path::PathBuf;
 #[derive(Serialize, Deserialize, Debug, Clone)]
 pub struct Workspace {
     pub parsers: toml::Spanned<Vec<Parser>>,
-    pub tests: Vec<TestDir>,
+    pub tests: Vec<Test>,
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone)]
@@ -35,13 +35,20 @@ fn default_recovery_kind() -> RecoveryKind {
 // are source generators, and files which contain a list of strings each to be parsed as
 // it's own file... So the reason TestKind is like this is for future expansion.
 // We should consider having a trait for it...
-#[derive(Serialize, Deserialize, Debug, Clone)]
+#[derive(Serialize, Deserialize, Debug, Clone, Eq, PartialEq)]
 pub enum TestKind {
+    // path of glob e.g. "tests/pass/**"
     Dir(String),
+    Toml {
+        /// Should match a Parser.extension
+        parser_extension: String,
+        /// An extension to be interpreted as toml tests
+        toml_test_extension: String,
+    },
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone)]
-pub struct TestDir {
+pub struct Test {
     pub kind: toml::Spanned<TestKind>,
     pub pass: bool,
 }
diff --git a/vscode/src/extension.ts b/vscode/src/extension.ts
index 7d29ad9..efa29f3 100644
--- a/vscode/src/extension.ts
+++ b/vscode/src/extension.ts
@@ -20,9 +20,13 @@ import { execFileSync } from 'child_process';
 let lspClient: LanguageClient;
 
 interface Parser { l_file: string, y_file: string, extension: string }
+
+interface TomlTest {Toml: {parser_extension: string, toml_test_extension: string}};
+interface DirTest {Dir: string};
+interface ParseTest {kind: TomlTest | DirTest, pass: boolean};
 interface TomlWorkspace {
     parsers: Parser[],
-    tests: {dir: string, pass: boolean}
+    tests: ParseTest[],
 };
 
 
@@ -46,7 +50,7 @@ export function activate(context: vscode.ExtensionContext) {
     const lsp_path_relative = path.resolve(path.join(context.extensionPath, "bin"), "nimbleparse_lsp");
     const lsp_path_relative_exe = path.resolve(path.join(context.extensionPath, "bin"), "nimbleparse_lsp.exe");
     // Try and find it relative to the extension, or fall back to the PATH.
-    const lsp_path = fs.existsSync(lsp_path_relative) ? lsp_path_relative : (fs.existsSync(lsp_path_relative_exe) ? lsp_path_relative_exe : "nimbleparse_lsp");
+    const outputChannel = vscode.window.createOutputChannel("nimbleparse_lsp");const lsp_path = fs.existsSync(lsp_path_relative) ? lsp_path_relative : (fs.existsSync(lsp_path_relative_exe) ? lsp_path_relative_exe : "nimbleparse_lsp");
 
     // This doesn't quite work if we have a project `foo/`
     // and a `foo/bar/nimbleparse.toml`.
@@ -71,6 +75,20 @@ export function activate(context: vscode.ExtensionContext) {
 	    return;
     }
 
+    var testDirs: string[] = [];
+    tomls?.forEach(
+        (toml) => {
+            toml.workspace.tests.forEach(
+                (test) => {
+                    let foo = test.kind as DirTest;
+                    if (foo.Dir != undefined) {
+                        testDirs.push(toml.folder + '/' + foo.Dir)
+                    }
+                }
+            )
+        }
+    );
+
     var dynSelector = tomls?.flatMap(
         (toml) => toml.workspace.parsers.flatMap(
             (parser: Parser) => ([{
@@ -84,7 +102,21 @@ export function activate(context: vscode.ExtensionContext) {
         )
     );
 
-    const outputChannel = vscode.window.createOutputChannel("nimbleparse_lsp");
+    testDirs.forEach(
+        (test_dir) => {
+            tomls?.forEach(
+                (toml) => toml.workspace.tests.forEach(
+                    (test) => {
+                        let foo = test.kind as TomlTest;
+                        if (foo.Toml != undefined) {
+                            dynSelector.push({pattern: test_dir + '/*' + foo.Toml.toml_test_extension })
+                        }
+                    }
+                )
+            )
+        }
+    );
+
     const lsp_exec: Executable = {
         command: lsp_path,
         args: ["--server"],