[IMP] qweb: add support for template strings

in inline expressions, such as t-esc or t-value.

closes #746

src/qweb/expression_parser.ts

@@ -57,6 +57,7 @@ type TKind =
   | "RIGHT_PAREN"
   | "COMMA"
   | "VALUE"
+  | "TEMPLATE_STRING"
   | "SYMBOL"
   | "OPERATOR"
   | "COLON";
@@ -67,6 +68,7 @@ interface Token {
   originalValue?: string;
   size?: number;
   varName?: string;
+  replace?: Function;
 }
 
 const STATIC_TOKEN_MAP: { [key: string]: TKind } = Object.assign(Object.create(null), {
@@ -89,7 +91,7 @@ type Tokenizer = (expr: string) => Token | false;
 let tokenizeString: Tokenizer = function (expr) {
   let s = expr[0];
   let start = s;
-  if (s !== "'" && s !== '"') {
+  if (s !== "'" && s !== '"' && s !== "`") {
     return false;
   }
   let i = 1;
@@ -111,6 +113,17 @@ let tokenizeString: Tokenizer = function (expr) {
     throw new Error("Invalid expression");
   }
   s += start;
+  if (start === "`") {
+    return {
+      type: "TEMPLATE_STRING",
+      value: s,
+      replace(replacer) {
+        return s.replace(/\$\{(.*?)\}/g, (match, group) => {
+          return "${" + replacer(group) + "}";
+        });
+      },
+    };
+  }
   return { type: "VALUE", value: s };
 };
 
@@ -267,6 +280,9 @@ export function compileExprToArray(expr: string, scope: { [key: string]: QWebVar
         }
       }
     }
+    if (token.type === "TEMPLATE_STRING") {
+      token.value = token.replace((expr) => compileExpr(expr, scope));
+    }
     if (nextToken && nextToken.type === "OPERATOR" && nextToken.value === "=>") {
       if (token.type === "RIGHT_PAREN") {
         let j = i - 1;

tests/qweb/__snapshots__/qweb.test.ts.snap

@@ -1236,6 +1236,55 @@ exports[`static templates empty div 1`] = `
 }"
 `;
 
+exports[`static templates inline template string in t-esc 1`] = `
+"function anonymous(context, extra
+) {
+    // Template name: \\"test\\"
+    let scope = Object.create(context);
+    let result;
+    let h = this.h;
+    let _1 = \`text\`;
+    if (_1 != null) {
+        let vn2 = {text: _1};
+        result = vn2
+    }
+    return result;
+}"
+`;
+
+exports[`static templates inline template string with content in t-esc 1`] = `
+"function anonymous(context, extra
+) {
+    // Template name: \\"test\\"
+    let scope = Object.create(context);
+    let result;
+    let h = this.h;
+    scope.v = 1;
+    let _1 = \`text\${scope.v}\`;
+    if (_1 != null) {
+        let vn2 = {text: _1};
+        result = vn2
+    }
+    return result;
+}"
+`;
+
+exports[`static templates inline template string with variable in context 1`] = `
+"function anonymous(context, extra
+) {
+    // Template name: \\"test\\"
+    let scope = Object.create(context);
+    let result;
+    let h = this.h;
+    let _1 = \`text \${scope['v']}\`;
+    if (_1 != null) {
+        let vn2 = {text: _1};
+        result = vn2
+    }
+    return result;
+}"
+`;
+
 exports[`static templates properly handle comments 1`] = `
 "function anonymous(context, extra
 ) {

tests/qweb/qweb.test.ts

@@ -31,6 +31,21 @@ describe("static templates", () => {
     expect(renderToString(qweb, "test", { text: "hello vdom" })).toBe("hello vdom");
   });
 
+  test("inline template string in t-esc", () => {
+    qweb.addTemplate("test", '<t><t t-esc="`text`"/></t>');
+    expect(renderToString(qweb, "test")).toBe("text");
+  });
+
+  test("inline template string with content in t-esc", () => {
+    qweb.addTemplate("test", '<t><t t-set="v" t-value="1"/><t t-esc="`text${v}`"/></t>');
+    expect(renderToString(qweb, "test")).toBe("text1");
+  });
+
+  test("inline template string with variable in context", () => {
+    qweb.addTemplate("test", '<t><t t-esc="`text ${v}`"/></t>');
+    expect(renderToString(qweb, "test", { v: "from context" })).toBe("text from context");
+  });
+
   test("simple string, with some dynamic value", () => {
     qweb.addTemplate("test", '<t>hello <t t-esc="text"/></t>');
     expect(renderToString(qweb, "test", { text: "vdom" })).toBe("hello vdom");

tests/qweb/qweb_expressions.test.ts

@@ -206,4 +206,10 @@ describe("expression evaluation", () => {
     expect(compileExpr("{a,b}", {})).toBe("{a:scope['a'],b:scope['b']}");
     expect(compileExpr("{a,b:3,c}", {})).toBe("{a:scope['a'],b:3,c:scope['c']}");
   });
+
+  test("template strings", () => {
+    expect(compileExpr("`hey`", {})).toBe("`hey`");
+    expect(compileExpr("`hey ${you}`", {})).toBe("`hey ${scope['you']}`");
+    expect(compileExpr("`hey ${1 + 2}`", {})).toBe("`hey ${1+2}`");
+  });
 });

tools/playground/app.js

@@ -72,7 +72,7 @@ if __name__ == "__main__":
  * Make an iframe, with all the js, css and xml properly injected.
  */
 function makeCodeIframe(js, css, xml) {
-  const sanitizedXML = xml.replace(/<!--[\s\S]*?-->/g, "");
+  const sanitizedXML = xml.replace(/<!--[\s\S]*?-->/g, "").replace(/`/g, '\\\`');
 
 
   // create iframe