Support for "@import".

Author: gkellogg

CHANGELOG.md

@@ -30,6 +30,9 @@
 ### Changed
 - `isKeyword()` optimization for non-keyword fast path.
 
+### Added
+- Support for `"@import"`.
+
 ## 2.0.1 - 2019-12-10
 
 ### Fixed

lib/context.js

@@ -266,6 +266,53 @@ api.process = async ({
       defined.set('@propagate', true);
     }
 
+    // handle @import
+    if('@import' in ctx) {
+      const value = ctx['@import'];
+      if(activeCtx.processingMode === 'json-ld-1.0') {
+        throw new JsonLdError(
+          'Invalid JSON-LD syntax; @import not compatible with ' +
+          activeCtx.processingMode,
+          'jsonld.SyntaxError',
+          {code: 'invalid context member', context: ctx});
+      }
+      if(!_isString(value)) {
+        throw new JsonLdError(
+          'Invalid JSON-LD syntax; @import must be a string.',
+          'jsonld.SyntaxError',
+          {code: 'invalid @import value', context: localCtx});
+      }
+
+      // resolve contexts
+      const resolvedImport = await options.contextResolver.resolve({
+        context: value,
+        documentLoader: options.documentLoader,
+        base: options.base
+      });
+      if(resolvedImport.length !== 1) {
+        throw new JsonLdError(
+          'Invalid JSON-LD syntax; @import must reference a single context.',
+          'jsonld.SyntaxError',
+          {code: 'invalid remote context', context: localCtx});
+      }
+      const importCtx = resolvedImport[0].document;
+      if('@import' in importCtx) {
+        throw new JsonLdError(
+          'Invalid JSON-LD syntax; imported context must not include @import.',
+          'jsonld.SyntaxError',
+          {code: 'invalid context member', context: localCtx});
+      }
+
+      // merge ctx into importCtx and replace rval with the result
+      for(const key in importCtx) {
+        if(!(key in ctx)) {
+          ctx[key] = importCtx[key];
+        }
+      }
+
+      defined.set('@import', true);
+    }
+
     // handle @protected; determine whether this sub-context is declaring
     // all its terms to be "protected" (exceptions can be made on a
     // per-definition basis)

tests/test-common.js

@@ -103,14 +103,6 @@ const TEST_TYPES = {
         /expand-manifest.jsonld#thc05$/,
         // remote
         /remote-doc-manifest.jsonld#t0013$/, // HTML
-        // @import
-        /expand-manifest.jsonld#tso01$/,
-        /expand-manifest.jsonld#tso02$/,
-        /expand-manifest.jsonld#tso03$/,
-        /expand-manifest.jsonld#tso05$/,
-        /expand-manifest.jsonld#tso06$/,
-        // @import and protected
-        /expand-manifest.jsonld#tso07$/,
         // context merging
         /expand-manifest.jsonld#tso08$/,
         /expand-manifest.jsonld#tso10$/,
@@ -341,14 +333,6 @@ const TEST_TYPES = {
         /toRdf-manifest.jsonld#te075$/,
         /toRdf-manifest.jsonld#te111$/,
         /toRdf-manifest.jsonld#te112$/,
-        // @import
-        /toRdf-manifest.jsonld#tso01$/,
-        /toRdf-manifest.jsonld#tso02$/,
-        /toRdf-manifest.jsonld#tso03$/,
-        /toRdf-manifest.jsonld#tso05$/,
-        /toRdf-manifest.jsonld#tso06$/,
-        // @import and protected
-        /toRdf-manifest.jsonld#tso07$/,
         // context merging
         /toRdf-manifest.jsonld#tso08$/,
         /toRdf-manifest.jsonld#tso10$/,