update some compiler error messages

src/compiler/compile/compiler_errors.ts

@@ -248,7 +248,7 @@ export default {
 	},
 	invalid_const_placement: {
 		code: 'invalid-const-placement',
-		message: '{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> and <Component>'
+		message: '{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> or <Component>'
 	},
 	invalid_const_declaration: (name: string) => ({
 		code: 'invalid-const-declaration',
@@ -256,10 +256,10 @@ export default {
 	}),
 	invalid_const_update: (name: string) => ({
 		code: 'invalid-const-update',
-		message: `'${name}' is declared using {@const ...} and it is read-only`
+		message: `'${name}' is declared using {@const ...} and is read-only`
 	}),
-	cyclical_constant_tags: (cycle: string[]) => ({
+	cyclical_const_tags: (cycle: string[]) => ({
-		code: 'cyclical-constant-tags',
+		code: 'cyclical-const-tags',
 		message: `Cyclical dependency detected: ${cycle.join(' → ')}`
 	})
 };

src/compiler/compile/nodes/shared/get_const_tags.ts

@@ -68,7 +68,7 @@ function sort_consts_nodes(consts_nodes: ConstTag[], component: Component) {
   if (cycle && cycle.length) {
     const nodeList = lookup.get(cycle[0]);
     const node = nodeList[0];
-    component.error(node.node, compiler_errors.cyclical_constant_tags(cycle));
+    component.error(node.node, compiler_errors.cyclical_const_tags(cycle));
   }
 
   const add_node = (node: ConstNode) => {

test/validator/samples/const-tag-cyclical/errors.json

@@ -1,6 +1,6 @@
 [
 	{
-		"code": "cyclical-constant-tags",
+		"code": "cyclical-const-tags",
 		"message": "Cyclical dependency detected: b → c → b",
 		"start": { "line": 6, "column": 2, "character": 61 },
 		"end": { "line": 6, "column": 20, "character": 79 },

test/validator/samples/const-tag-placement-1/errors.json

@@ -1,7 +1,7 @@
 [
 	{
 		"code": "invalid-const-placement",
-		"message": "{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> and <Component>",
+		"message": "{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> or <Component>",
 		"start": { "line": 5, "column": 0, "character": 36 },
 		"end": { "line": 5, "column": 18, "character": 54 },
 		"pos": 36

test/validator/samples/const-tag-placement-2/errors.json

@@ -1,7 +1,7 @@
 [
 	{
 		"code": "invalid-const-placement",
-		"message": "{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> and <Component>",
+		"message": "{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> or <Component>",
 		"start": { "line": 6, "column": 2, "character": 46 },
 		"end": { "line": 6, "column": 20, "character": 64 },
 		"pos": 46

test/validator/samples/const-tag-placement-3/errors.json

@@ -1,7 +1,7 @@
 [
 	{
 		"code": "invalid-const-placement",
-		"message": "{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> and <Component>",
+		"message": "{@const} must be the immediate child of {#each}, {:then}, {:catch}, <svelte:fragment> or <Component>",
 		"start": { "line": 7, "column": 4, "character": 63 },
 		"end": { "line": 7, "column": 18, "character": 77 },
 		"pos": 63

test/validator/samples/const-tag-readonly-1/errors.json

@@ -1,7 +1,7 @@
 [
 	{
 		"code": "invalid-const-update",
-		"message": "'b' is declared using {@const ...} and it is read-only",
+		"message": "'b' is declared using {@const ...} and is read-only",
 		"start": { "line": 7, "column": 26, "character": 106 },
 		"end": { "line": 7, "column": 30, "character": 110 },
 		"pos": 106