New Grammars Compiler (#3915)

* grammars: Update several grammars with compat issues

* [WIP] Add new grammar conversion tools

* Wrap in a Docker script

* Proper Dockerfile support

* Add Javadoc grammar

* Remove NPM package.json

* Remove superfluous test

This is now always checked by the grammars compiler

* Update JSyntax grammar to new submodule

* Approve Javadoc license

* grammars: Remove checked-in dependencies

* grammars: Add regex checks to the compiler

* grammars: Point Oz to its actual submodule

* grammars: Refactor compiler to group errors by repo

* grammars: Cleanups to error reporting

tools/grammars/compiler/errors.go

@@ -0,0 +1,85 @@
+package compiler
+
+import "fmt"
+import "strings"
+
+type ConversionError struct {
+	Path string
+	Err  error
+}
+
+func (err *ConversionError) Error() string {
+	return fmt.Sprintf(
+		"Grammar conversion failed. File `%s` failed to parse: %s",
+		err.Path, err.Err)
+}
+
+type DuplicateScopeError struct {
+	Original  *Repository
+	Duplicate string
+}
+
+func (err *DuplicateScopeError) Error() string {
+	return fmt.Sprintf(
+		"Duplicate scope in repository: scope `%s` was already defined in %s",
+		err.Duplicate, err.Original)
+}
+
+type MissingScopeError struct {
+	Scope string
+}
+
+func (err *MissingScopeError) Error() string {
+	return fmt.Sprintf(
+		"Missing scope in repository: `%s` is listed in grammars.yml but cannot be found",
+		err.Scope)
+}
+
+type UnexpectedScopeError struct {
+	File  *LoadedFile
+	Scope string
+}
+
+func (err *UnexpectedScopeError) Error() string {
+	return fmt.Sprintf(
+		"Unexpected scope in repository: `%s` declared in %s was not listed in grammars.yml",
+		err.Scope, err.File)
+}
+
+type MissingIncludeError struct {
+	File    *LoadedFile
+	Include string
+}
+
+func (err *MissingIncludeError) Error() string {
+	return fmt.Sprintf(
+		"Missing include in grammar: %s attempts to include `%s` but the scope cannot be found",
+		err.File, err.Include)
+}
+
+type UnknownKeysError struct {
+	File *LoadedFile
+	Keys []string
+}
+
+func (err *UnknownKeysError) Error() string {
+	var keys []string
+	for _, k := range err.Keys {
+		keys = append(keys, fmt.Sprintf("`%s`", k))
+	}
+
+	return fmt.Sprintf(
+		"Unknown keys in grammar: %s contains invalid keys (%s)",
+		err.File, strings.Join(keys, ", "))
+}
+
+type InvalidRegexError struct {
+	File *LoadedFile
+	Err  error
+}
+
+func (err *InvalidRegexError) Error() string {
+	return fmt.Sprintf(
+		"Invalid regex in grammar: %s contains a malformed regex (%s)",
+		err.File, err.Err)
+}