Add variables for xml.fileAssociations

Adds three variables that can be used in `xml.fileAssociations`:
 * ${workspaceFolder}
 * ${fileDirname}
 * ${fileBasenameNoExtension}

These variables can be used for both the `pattern` and the `systemId`.

Closes #307

Signed-off-by: David Thompson <davthomp@redhat.com>

Author: datho7561

docs/Validation.md

@@ -199,6 +199,18 @@ Please note that you can use wildcards in the pattern (ex: `foo*.xml`):
 
 In this case, all XML files that start with foo and end with .xml will be associated with the XSD (foo1.xml, foo2.xml, etc)
 
+You can also use the following three variables in either the `pattern` or `systemId`:
+
+ | Variable                    | Meaning                                                                  |
+ | --------------------------- | ------------------------------------------------------------------------ |
+ | ${workspaceFolder}          | The absolute path to root folder of the workspace that is currently open |
+ | ${fileDirname}              | The absolute path to the folder of the file that is currently opened     |
+ | ${fileBasenameNoExtension}  | The current opened file's basename with no file extension                |
+
+If one of the variables for an association can't be expanded (eg. because vscode is opened in rootless mode),
+the association is ignored.
+This feature is specific to the VSCode client.
+
 ## Validation with DTD grammar
 
 To associate your XML with a DTD grammar you can use several strategies:
@@ -322,7 +334,17 @@ Please note that you can use wildcards in the pattern (ex: `foo*.xml`):
 
 In this case, all XML files that start with foo and end with .xml will be associated with the DTD (foo1.xml, foo2.xml, etc)
 
+You can also use the following three variables in either the `pattern` or `systemId`:
+
+ | Variable                    | Meaning                                                                  |
+ | --------------------------- | ------------------------------------------------------------------------ |
+ | ${workspaceFolder}          | The absolute path to root folder of the workspace that is currently open |
+ | ${fileDirname}              | The absolute path to the folder of the file that is currently opened     |
+ | ${fileBasenameNoExtension}  | The current opened file's basename with no file extension                |
 
+If one of the variables for an association can't be expanded (eg. because vscode is opened in rootless mode),
+the association is ignored.
+This feature is specific to the VSCode client.
 
 # Other Validation Settings
 

src/extension.ts

@@ -10,17 +10,17 @@
  *  Microsoft Corporation - Auto Closing Tags
  */
 
-import { prepareExecutable } from './javaServerStarter';
-import { LanguageClientOptions, RevealOutputChannelOn, LanguageClient, DidChangeConfigurationNotification, RequestType, TextDocumentPositionParams, ReferencesRequest, NotificationType, MessageType } from 'vscode-languageclient';
-import * as requirements from './requirements';
-import { languages, IndentAction, workspace, window, commands, ExtensionContext, TextDocument, Position, LanguageConfiguration, Uri, extensions, Command } from "vscode";
-import * as path from 'path';
 import * as os from 'os';
-import { activateTagClosing, AutoCloseResult } from './tagClosing';
+import * as path from 'path';
+import { Command, commands, ExtensionContext, extensions, IndentAction, LanguageConfiguration, languages, Position, TextDocument, Uri, window, workspace, WorkspaceFolder } from "vscode";
+import { DidChangeConfigurationNotification, LanguageClient, LanguageClientOptions, MessageType, NotificationType, ReferencesRequest, RequestType, RevealOutputChannelOn, TextDocumentPositionParams } from 'vscode-languageclient';
 import { Commands } from './commands';
-import { onConfigurationChange, subscribeJDKChangeConfiguration } from './settings';
-import { collectXmlJavaExtensions, onExtensionChange } from './plugin';
+import { prepareExecutable } from './javaServerStarter';
 import { markdownPreviewProvider } from "./markdownPreviewProvider";
+import { collectXmlJavaExtensions, onExtensionChange } from './plugin';
+import * as requirements from './requirements';
+import { getXMLConfiguration, onConfigurationChange, subscribeJDKChangeConfiguration } from './settings';
+import { activateTagClosing, AutoCloseResult } from './tagClosing';
 
 export interface ScopeInfo {
   scope: "default" | "global" | "workspace" | "folder";
@@ -249,6 +249,16 @@ export function activate(context: ExtensionContext) {
         }));
       }
 
+      // When the current document changes, update ${fileDirname} and ${fileBasenameNoExtension}
+      // for the file associations, (but only if these variables are referenced),
+      // and send the updated settings to the server
+      context.subscriptions.push(window.onDidChangeActiveTextEditor(() => {
+        if (isFileAssocReferencesCurrentFile()) {
+          languageClient.sendNotification(DidChangeConfigurationNotification.type, { settings: getXMLSettings(requirements.java_home) });
+          onConfigurationChange();
+        }
+      }));
+
       const api: XMLExtensionApi = {
         // add API set catalogs to internal memory
         addXMLCatalogs: (catalogs: string[]) => {
@@ -349,14 +359,70 @@ export function activate(context: ExtensionContext) {
         xml['xml']['catalogs'].push(catalog);
       }
     })
-    externalXmlSettings.xmlFileAssociations.forEach(element => {
-      if (!xml['xml']['fileAssociations'].some(fileAssociation => fileAssociation.systemId === element.systemId)) {
-        xml['xml']['fileAssociations'].push(element);
-      }
-    });
+    const variableSubstitutedAssociations: XMLFileAssociation[] =
+      xml['xml']['fileAssociations'].map((association: XMLFileAssociation): XMLFileAssociation => {
+
+        const currentFile: TextDocument = window.activeTextEditor.document;
+        const currentFileUri: string = currentFile && currentFile.uri.fsPath;
+        const currentWorkspace: WorkspaceFolder = workspace.getWorkspaceFolder(currentFile && currentFile.uri);
+        const currentWorkspaceUri: string = (currentWorkspace && currentWorkspace.uri.fsPath)
+          || (workspace.workspaceFolders && workspace.workspaceFolders[0].uri.fsPath);
+
+        if (!currentWorkspaceUri
+          && (association.pattern.indexOf('&{workspaceFolder}') >= 0
+            || association.systemId.indexOf('&{workspaceFolder}') >= 0)) {
+          return;
+        }
+
+        if (!currentFileUri
+          && (association.pattern.indexOf('&{fileDirname}') >= 0
+            || association.systemId.indexOf('&{fileDirname}') >= 0
+            || association.pattern.indexOf('&{fileBasenameNoExtension}') >= 0
+            || association.systemId.indexOf('&{fileBasenameNoExtension}') >= 0)) {
+          return;
+        }
+
+        /**
+         * Returns the string with the values for:
+         * * ${workspaceFolder}
+         * * ${fileDirname}
+         * * ${fileBasenameNoExtension}
+         * substituted into the string
+         *
+         * @param val the value to substitute the variables into
+         * @return the string with values for the variables substituted into the string
+         */
+        const subVars = (val: string): string => {
+          let newVal: string = val.replace(/\$\{workspaceFolder\}/g, currentWorkspaceUri);
+          newVal = newVal.replace(/\$\{fileDirname\}/g, path.dirname(currentFileUri));
+          newVal = newVal.replace(/\$\{fileBasenameNoExtension\}/g, path.basename(currentFileUri, path.extname(currentFileUri)));
+          return newVal;
+        }
+
+        return {
+          pattern: subVars(association.pattern),
+          systemId: subVars(association.systemId)
+        };
+      });
+    xml['xml']['fileAssociations'] = [...variableSubstitutedAssociations];
 
     return xml;
   }
+
+  /**
+   * Returns true if the the XML settings contain a file association with a variable reference to the current file and false otherwise
+   *
+   * @return true if the the XML settings contain a file association with a variable reference to the current file and false otherwise
+   */
+  function isFileAssocReferencesCurrentFile(): boolean {
+    for (const assoc of getXMLConfiguration().get('fileAssociations') as XMLFileAssociation[]) {
+      if (assoc.pattern.indexOf('${fileDirname}') >= 0 || assoc.pattern.indexOf('${fileBasenameNoExtension}') >= 0
+        || assoc.systemId.indexOf('${fileDirname}') >= 0 || assoc.systemId.indexOf('${fileBasenameNoExtension}') >= 0) {
+        return true;
+      }
+    }
+    return false;
+  }
 }
 
 export function deactivate(): void {