Add internal tests to xss lab

docs/labs/xss.js

@@ -2,40 +2,65 @@ info =
 {
   hints: [
     {
-      absent: "autoescape",
-      text: "Add an `autoescape=` parameter."
+      present: "(Autoescape|AUTOESCAPE)",
+      text: "The name `autoescape` must be in all lowercase.",
+      examples: [
+        [ "Autoescape" ],
+      ],
     },
     {
-      present: String.raw`autoescape [^:\x20]`,
-      text: "The name `autoescape` needs to be followed by `=`."
+      present: "([Aa]uto_[Ee]scape|AUTO_ESCAPE)",
+      text: "Use `autoescape` in all lowercase with no underscores.",
+      examples: [
+        [ "auto_escape" ],
+      ],
     },
     {
-      present: "(Autoescape|AUTOESCAPE)",
-      text: "The name `autoescape` must be in all lowercase."
+      absent: "autoescape",
+      text: "Add an `autoescape=` parameter.",
+      examples: [
+        [ "" ],
+      ],
     },
     {
-      present: "([Aa]uto_[Ee]scape|AUTO_ESCAPE)",
-      text: "Use `autoescape` in all lowercase with no underscores."
+      present: 'autoescape',
+      absent: String.raw`autoescape\x20*=`,
+      text: "The name `autoescape` needs to be followed by `=`.",
+      examples: [
+        [ "autoescape" ],
+      ],
     },
     {
       present: String.raw`\| safe`,
       index: 1,
-      text: "The text `| safe` indicates that this text is trusted and should not be escaped further. However, in context this data could be provided from an attacker and is NOT safe. Remove the marking."
+      text: "The text `| safe` indicates that this text is trusted and should not be escaped further. However, in context this data could be provided from an attacker and is NOT safe. Remove the marking.",
+      examples: [
+        [ null, "  <h1>Hello {{ person | safe }}!</h1>" ],
+      ],
     },
     {
       present: String.raw`\|`,
       index: 1,
-      text: "The `|` is used to separate the computed value from the safe marking, but we will not use that marking. Remove the vertical bar."
+      text: "The `|` is used to separate the computed value from the safe marking, but we will not use that marking. Remove the vertical bar.",
+      examples: [
+        [ null, "  <h1>Hello {{ person | }}!</h1>" ],
+      ],
     },
     {
       present: String.raw`Markup \(.*\+.*\)`,
       index: 2,
-      text: "Having a concatenation (+) *inside* the call to Markup is a vulnerability. The call to Markup presumes we are passing text that is *not* supposed be escaped. If it is supposed to be escaped, it should be concatenated outside the initial construction of the Markup object."
+      text: "Having a concatenation (+) *inside* the call to Markup is a vulnerability. The call to Markup presumes we are passing text that is *not* supposed be escaped. If it is supposed to be escaped, it should be concatenated outside the initial construction of the Markup object.",
+      examples: [
+        [ null, null, "  result = Markup('Original name=' + name)" ],
+      ],
     },
     {
       absent: String.raw`\+`,
       index: 2,
-      text: "Our expected answer includes concatentation using `+`. We expect something like `Markup('Original name='` followed by `+` followed by the variable containing the data that needs to be escaped."
+      text: "Our expected answer includes concatentation using `+`. We expect something like `Markup('Original name='` followed by `+` followed by the variable containing the data that needs to be escaped.",
+      examples: [
+        [ null, null, '  result = Markup(f"Original name={name}' ],
+      ],
     },
   ],
   expected: [
@@ -44,6 +69,8 @@ info =
     `result = Markup('Original name=') + name`
   ],
   correct: [
+     // Python PEP 8 recommends no space '=' around keyword use, but
+     // Python allows it, so we will too.
      String.raw`\s* autoescape = select_autoescape \( \) \s*`,
      String.raw`\s* < h1 >Hello\x20{{ person }}!< /h1 > \s*`,
      String.raw`\s* result = Markup \( ('Original name='|"Original name=") \) \+ name \s*`