1 files changed, 132 insertions, 6 deletions

diff --git a/language-web/src/main/js/editor/xtextServiceResults.ts b/language-web/src/main/js/editor/xtextServiceResults.ts
index 8a4afa40..6c3d9daf 100644
--- a/language-web/src/main/js/editor/xtextServiceResults.ts
+++ b/language-web/src/main/js/editor/xtextServiceResults.ts
@@ -22,20 +22,32 @@ export const VALID_CONFLICTS = ['invalidStateId', 'canceled'] as const;
 
 export type Conflict = typeof VALID_CONFLICTS[number];
 
+export function isConflict(value: unknown): value is Conflict {
+  return typeof value === 'string' && VALID_CONFLICTS.includes(value as Conflict);
+}
+
 export interface IServiceConflictResult {
   conflict: Conflict;
 }
 
 export function isServiceConflictResult(result: unknown): result is IServiceConflictResult {
   const serviceConflictResult = result as IServiceConflictResult;
-  return typeof serviceConflictResult.conflict === 'string'
-    && VALID_CONFLICTS.includes(serviceConflictResult.conflict);
+  return typeof serviceConflictResult === 'object'
+    && isConflict(serviceConflictResult.conflict);
+}
+
+export function isInvalidStateIdConflictResult(result: unknown): boolean {
+  return isServiceConflictResult(result) && result.conflict === 'invalidStateId';
 }
 
 export const VALID_SEVERITIES = ['error', 'warning', 'info', 'ignore'] as const;
 
 export type Severity = typeof VALID_SEVERITIES[number];
 
+export function isSeverity(value: unknown): value is Severity {
+  return typeof value === 'string' && VALID_SEVERITIES.includes(value as Severity);
+}
+
 export interface IIssue {
   description: string;
 
@@ -54,8 +66,7 @@ export function isIssue(value: unknown): value is IIssue {
   const issue = value as IIssue;
   return typeof issue === 'object'
     && typeof issue.description === 'string'
-    && typeof issue.severity === 'string'
-    && VALID_SEVERITIES.includes(issue.severity)
+    && isSeverity(issue.severity)
     && typeof issue.line === 'number'
     && typeof issue.column === 'number'
     && typeof issue.offset === 'number'
@@ -66,9 +77,124 @@ export interface IValidationResult {
   issues: IIssue[];
 }
 
+function isArrayOfType<T>(value: unknown, check: (entry: unknown) => entry is T): value is T[] {
+  return Array.isArray(value) && (value as T[]).every(check);
+}
+
 export function isValidationResult(result: unknown): result is IValidationResult {
   const validationResult = result as IValidationResult;
   return typeof validationResult === 'object'
-    && Array.isArray(validationResult.issues)
-    && validationResult.issues.every(isIssue);
+    && isArrayOfType(validationResult.issues, isIssue);
+}
+
+export interface IReplaceRegion {
+  offset: number;
+
+  length: number;
+
+  text: string;
+}
+
+export function isReplaceRegion(value: unknown): value is IReplaceRegion {
+  const replaceRegion = value as IReplaceRegion;
+  return typeof replaceRegion === 'object'
+    && typeof replaceRegion.offset === 'number'
+    && typeof replaceRegion.length === 'number'
+    && typeof replaceRegion.text === 'string';
+}
+
+export interface ITextRegion {
+  offset: number;
+
+  length: number;
+}
+
+export function isTextRegion(value: unknown): value is ITextRegion {
+  const textRegion = value as ITextRegion;
+  return typeof textRegion === 'object'
+    && typeof textRegion.offset === 'number'
+    && typeof textRegion.length === 'number';
+}
+
+export const VALID_XTEXT_CONTENT_ASSIST_ENTRY_KINDS = [
+  'TEXT',
+  'METHOD',
+  'FUNCTION',
+  'CONSTRUCTOR',
+  'FIELD',
+  'VARIABLE',
+  'CLASS',
+  'INTERFACE',
+  'MODULE',
+  'PROPERTY',
+  'UNIT',
+  'VALUE',
+  'ENUM',
+  'KEYWORD',
+  'SNIPPET',
+  'COLOR',
+  'FILE',
+  'REFERENCE',
+  'UNKNOWN',
+] as const;
+
+export type XtextContentAssistEntryKind = typeof VALID_XTEXT_CONTENT_ASSIST_ENTRY_KINDS[number];
+
+export function isXtextContentAssistEntryKind(
+  value: unknown,
+): value is XtextContentAssistEntryKind {
+  return typeof value === 'string'
+    && VALID_XTEXT_CONTENT_ASSIST_ENTRY_KINDS.includes(value as XtextContentAssistEntryKind);
+}
+
+export interface IContentAssistEntry {
+  prefix: string;
+
+  proposal: string;
+
+  label?: string;
+
+  description?: string;
+
+  documentation?: string;
+
+  escapePosition?: number;
+
+  textReplacements: IReplaceRegion[];
+
+  editPositions: ITextRegion[];
+
+  kind: XtextContentAssistEntryKind | string;
+}
+
+function isStringOrUndefined(value: unknown): value is string | undefined {
+  return typeof value === 'string' || typeof value === 'undefined';
+}
+
+function isNumberOrUndefined(value: unknown): value is number | undefined {
+  return typeof value === 'number' || typeof value === 'undefined';
+}
+
+export function isContentAssistEntry(value: unknown): value is IContentAssistEntry {
+  const entry = value as IContentAssistEntry;
+  return typeof entry === 'object'
+    && typeof entry.prefix === 'string'
+    && typeof entry.proposal === 'string'
+    && isStringOrUndefined(entry.label)
+    && isStringOrUndefined(entry.description)
+    && isStringOrUndefined(entry.documentation)
+    && isNumberOrUndefined(entry.escapePosition)
+    && isArrayOfType(entry.textReplacements, isReplaceRegion)
+    && isArrayOfType(entry.editPositions, isTextRegion)
+    && typeof entry.kind === 'string';
+}
+
+export interface IContentAssistResult extends IDocumentStateResult {
+  entries: IContentAssistEntry[];
+}
+
+export function isContentAssistResult(result: unknown): result is IContentAssistResult {
+  const contentAssistResult = result as IContentAssistResult;
+  return isDocumentStateResult(result)
+    && isArrayOfType(contentAssistResult.entries, isContentAssistEntry);
 }