From 631da3ac2761c9ef13ef56654ceb4cbcee76443c Mon Sep 17 00:00:00 2001
From: Dylan Piercey <dpiercey@ebay.com>
Date: Tue, 1 Mar 2022 09:05:48 -0700
Subject: [PATCH] feat: throw errors when using statement tags if not at
 concise root

---
 src/states/TAG_NAME.ts                        | 26 +++++++++++++++----
 .../statement-concise-only/expected.html      |  1 +
 .../statement-concise-only/input.htmljs       |  1 +
 .../statement-root-only/expected.html         |  3 +++
 .../autotest/statement-root-only/input.htmljs |  2 ++
 5 files changed, 28 insertions(+), 5 deletions(-)
 create mode 100644 test/autotest/statement-concise-only/expected.html
 create mode 100644 test/autotest/statement-concise-only/input.htmljs
 create mode 100644 test/autotest/statement-root-only/expected.html
 create mode 100644 test/autotest/statement-root-only/input.htmljs

diff --git a/src/states/TAG_NAME.ts b/src/states/TAG_NAME.ts
index 63cec8ca..27c50ed6 100644
--- a/src/states/TAG_NAME.ts
+++ b/src/states/TAG_NAME.ts
@@ -80,11 +80,27 @@ export const TAG_NAME: StateDefinition<TagNameMeta> = {
         if (tagName.expressions.length === 0) {
           if (this.matchAnyAtPos(tagName, ONLY_OPEN_TAGS)) {
             tag.openTagOnly = true;
-          } else if (
-            tag.concise &&
-            this.blockStack[0] === tag &&
-            this.matchAnyAtPos(tagName, EXPRESSION_TAGS)
-          ) {
+          } else if (this.matchAnyAtPos(tagName, EXPRESSION_TAGS)) {
+            if (!tag.concise) {
+              return this.emitError(
+                tagName,
+                "RESERVED_TAG_NAME",
+                `The "${this.read(
+                  tagName
+                )}" tag is reserved as a statement and cannot be used as an HTML tag.`
+              );
+            }
+
+            if (this.blockStack[0] !== tag) {
+              return this.emitError(
+                tagName,
+                "ROOT_TAG_ONLY",
+                `The "${this.read(
+                  tagName
+                )}" statement can only be used at the root of the template.`
+              );
+            }
+
             tag.statement = true;
             tag.openTagOnly = true;
             this.enterState(STATE.EXPRESSION, { terminatedByEOL: true });
diff --git a/test/autotest/statement-concise-only/expected.html b/test/autotest/statement-concise-only/expected.html
new file mode 100644
index 00000000..7fcb4a05
--- /dev/null
+++ b/test/autotest/statement-concise-only/expected.html
@@ -0,0 +1 @@
+error:"The \"static\" tag is reserved as a statement and cannot be used as an HTML tag." (code: "RESERVED_TAG_NAME")
diff --git a/test/autotest/statement-concise-only/input.htmljs b/test/autotest/statement-concise-only/input.htmljs
new file mode 100644
index 00000000..b1ef471c
--- /dev/null
+++ b/test/autotest/statement-concise-only/input.htmljs
@@ -0,0 +1 @@
+<static const x = 1/>
diff --git a/test/autotest/statement-root-only/expected.html b/test/autotest/statement-root-only/expected.html
new file mode 100644
index 00000000..485d8100
--- /dev/null
+++ b/test/autotest/statement-root-only/expected.html
@@ -0,0 +1,3 @@
+<div>
+    error:"The \"static\" statement can only be used at the root of the template." (code: "ROOT_TAG_ONLY")
+</div>
diff --git a/test/autotest/statement-root-only/input.htmljs b/test/autotest/statement-root-only/input.htmljs
new file mode 100644
index 00000000..adc69e09
--- /dev/null
+++ b/test/autotest/statement-root-only/input.htmljs
@@ -0,0 +1,2 @@
+div
+  static const x = 1