[FIX] parser: make t-on stricter

Before this commit, the `t-on` directive assumed that the next character
would be a -, and ignored it, so if someone would write `t-onclick` by
mistake, Owl would then add an event handler on the `lick` event,
instead of `click`.

With this commit, we improve the parser to make it stricter and fail if
there is no dash.

closes #1441

src/compiler/parser.ts

@@ -336,10 +336,10 @@ function parseDOMNode(node: Element, ctx: ParsingContext): AST | null {
 
   for (let attr of nodeAttrsNames) {
     const value = node.getAttribute(attr)!;
-    if (attr.startsWith("t-on")) {
+    if (attr === "t-on" || attr === "t-on-") {
-      if (attr === "t-on") {
       throw new OwlError("Missing event name with t-on directive");
     }
+    if (attr.startsWith("t-on-")) {
       on = on || {};
       on[attr.slice(5)] = value;
     } else if (attr.startsWith("t-model")) {

tests/compiler/parser.test.ts

@@ -1147,6 +1147,24 @@ describe("qweb parser", () => {
     });
   });
 
+  test("t-onclick without dash", async () => {
+    expect(() => parse(`<button t-onclick="add">Click</button>`)).toThrowError(
+      "Unknown QWeb directive: 't-onclick'"
+    );
+  });
+
+  test("t-on without event", async () => {
+    expect(() => parse(`<button t-on="add">Click</button>`)).toThrowError(
+      "Missing event name with t-on directive"
+    );
+  });
+
+  test("t-on- without event", async () => {
+    expect(() => parse(`<button t-on-="add">Click</button>`)).toThrowError(
+      "Missing event name with t-on directive"
+    );
+  });
+
   // ---------------------------------------------------------------------------
   // t-model
   // ---------------------------------------------------------------------------
@@ -1275,6 +1293,12 @@ describe("qweb parser", () => {
     });
   });
 
+  test("component with event handler", async () => {
+    expect(() => parse(`<MyComponent t-onclick="someMethod"/>`)).toThrowError(
+      "unsupported directive on Component: t-onclick"
+    );
+  });
+
   test("component with t-ref", async () => {
     expect(() => parse(`<MyComponent t-ref="something"/>`)).toThrow(
       "t-ref is no longer supported on components. Consider exposing only the public part of the component's API through a callback prop."