modified to display better error messages

Author: DonJayamanne

src/client/formatters/baseFormatter.ts

@@ -37,8 +37,27 @@ export abstract class BaseFormatter {
             }
             return getTextEditsFromPatch(document.getText(), data[1]);
         }).catch(error => {
-            this.outputChannel.appendLine(error);
-            throw new Error(`There was an error in formatting the document. View the Python output window for details.`);
+            this.handleError(this.Id, command, error);
         });
     }
+
+    protected handleError(expectedFileName: string, fileName: string, error: Error) {
+        let customError = "Formatting with ${this.Id} failed. Please install the formatter or turn it off.\n";
+
+        if (typeof (error) === "object" && error !== null && ((<any>error).code === "ENOENT" || (<any>error).code === 127)) {
+            // Check if we have some custom arguments such as "pylint --load-plugins pylint_django"
+            // Such settings are no longer supported
+            let stuffAfterFileName = fileName.substring(fileName.toUpperCase().lastIndexOf(expectedFileName) + expectedFileName.length);
+
+            // Ok if we have a space after the file name, this means we have some arguments defined and this isn't supported
+            if (stuffAfterFileName.trim().indexOf(" ")) {
+                customError = `Formatting failed, custom arguments in the 'python.formatting.${this.Id}Path' is not supported.\n` +
+                    `Custom arguments to the formatter can be defined in 'python.formatter.${this.Id}Args' setting of settings.json.\n` +
+                    "For further details, please see https://github.com/DonJayamanne/pythonVSCode/wiki/Troubleshooting-Linting#2-linting-with-xxx-failed-";
+            }
+        }
+
+        this.outputChannel.appendLine(`${customError}\n${error}`);
+        throw new Error(`There was an error in formatting the document. View the Python output window for details.`);
+    }
 }

src/client/linters/baseLinter.ts

@@ -64,7 +64,7 @@ export abstract class BaseLinter {
 
         return new Promise<ILintMessage[]>((resolve, reject) => {
             execPythonFile(command, args, cwd, true).then(data => {
-                outputChannel.clear();
+                outputChannel.append("#".repeat(10) + "Linting Output - " + this.Id + "#".repeat(10));
                 outputChannel.append(data);
                 var outputLines = data.split(/\r?\n/g);
                 var diagnostics: ILintMessage[] = [];
@@ -108,10 +108,29 @@ export abstract class BaseLinter {
 
                 resolve(diagnostics);
             }).catch(error => {
-                outputChannel.appendLine(`Linting with ${linterId} failed. If not installed please turn if off in settings.\n ${error}`);
-                window.showInformationMessage(`Linting with ${linterId} failed. If not installed please turn if off in settings. View Python output for details.`);
+                this.handleError(this.Id, command, error);
                 return [];
             });
         });
     }
+
+    protected handleError(expectedFileName: string, fileName: string, error: Error) {
+        let customError = "Linting with ${this.Id} failed. Please install the linter or turn it off.\n";
+
+        if (typeof (error) === "object" && error !== null && ((<any>error).code === "ENOENT" || (<any>error).code === 127)) {
+            // Check if we have some custom arguments such as "pylint --load-plugins pylint_django"
+            // Such settings are no longer supported
+            let stuffAfterFileName = fileName.substring(fileName.toUpperCase().lastIndexOf(expectedFileName) + expectedFileName.length);
+
+            // Ok if we have a space after the file name, this means we have some arguments defined and this isn't supported
+            if (stuffAfterFileName.trim().indexOf(" ")) {
+                customError = `Linting failed, custom arguments in the 'python.linting.${this.Id}Path' is not supported.\n` +
+                    `Custom arguments to the linters can be defined in 'python.linting.${this.Id}Args' setting of settings.json.\n` +
+                    "For further details, please see https://github.com/DonJayamanne/pythonVSCode/wiki/Troubleshooting-Linting#2-linting-with-xxx-failed-";
+            }
+        }
+
+        this.outputChannel.appendLine(`${customError}\n${error}`);
+        window.showInformationMessage(`${customError}. View Python output for details.`);
+    }
 }

src/client/linters/prospector.ts

@@ -41,12 +41,12 @@ export class Linter extends baseLinter.BaseLinter {
         let prospectorArgs = Array.isArray(this.pythonSettings.linting.prospectorArgs) ? this.pythonSettings.linting.prospectorArgs : [];
         return new Promise<baseLinter.ILintMessage[]>((resolve, reject) => {
             execPythonFile(prospectorPath, prospectorArgs.concat(["--absolute-paths", "--output-format=json", filePath]), this.workspaceRootPath, false).then(data => {
-                outputChannel.clear();
                 let parsedData: IProspectorResponse;
                 try {
                     parsedData = JSON.parse(data);
                 }
                 catch (ex) {
+                    outputChannel.append("#".repeat(10) + "Linting Output - " + this.Id + "#".repeat(10));
                     outputChannel.append(data);
                     return resolve([]);
                 }
@@ -77,8 +77,8 @@ export class Linter extends baseLinter.BaseLinter {
 
                 resolve(diagnostics);
             }).catch(error => {
-                outputChannel.appendLine(`Linting with ${linterId} failed.If not installed please turn if off in settings.\n ${error} `);
-                window.showInformationMessage(`Linting with ${linterId} failed.If not installed please turn if off in settings.View Python output for details.`);
+                this.handleError(this.Id, prospectorPath, error);
+                return [];
             });
         });
     }

src/client/linters/pydocstyle.ts

@@ -41,7 +41,7 @@ export class Linter extends baseLinter.BaseLinter {
         return new Promise<ILintMessage[]>((resolve, reject) => {
             var fileDir = path.dirname(filePath);
             execPythonFile(commandLine, args, this.workspaceRootPath, true).then(data => {
-                outputChannel.clear();
+                outputChannel.append("#".repeat(10) + "Linting Output - " + this.Id + "#".repeat(10));
                 outputChannel.append(data);
                 var outputLines = data.split(/\r?\n/g);
                 var diagnostics: ILintMessage[] = [];
@@ -91,8 +91,8 @@ export class Linter extends baseLinter.BaseLinter {
                 });
                 resolve(diagnostics);
             }, error => {
-                outputChannel.appendLine(`Linting with ${linterId} failed. If not installed please turn if off in settings.\n ${error}`);
-                window.showInformationMessage(`Linting with ${linterId} failed. If not installed please turn if off in settings. View Python output for details.`);
+                this.handleError(this.Id, commandLine, error);
+                return [];
             });
         });
     }

src/client/providers/jediProxy.ts

@@ -398,11 +398,11 @@ function onConfigChanged() {
         getPathFromPythonCommand(["-c", "import sys;print(sys.prefix)"]),
         // Python specific site packages
         getPathFromPythonCommand(["-c", "from distutils.sysconfig import get_python_lib; print(get_python_lib())"]),
-        // Python global site packages
+        // Python global site packages, as a fallback in case user hasn't installed them in custom environment
         getPathFromPythonCommand(["-m", "side", "--user-site"])
     ];
     Promise.all<string>(filePaths).then(paths => {
-        // additionalAutoCopletePaths = paths.filter(p => p.length > 0);
+        additionalAutoCopletePaths = paths.filter(p => p.length > 0);
     });
 }
 
@@ -414,9 +414,9 @@ function getConfig() {
         }
         return path.join(vscode.workspace.rootPath, extraPath);
     });
-
+    let distinctExtraPaths = extraPaths.concat(additionalAutoCopletePaths).filter((value, index, self) => self.indexOf(value) === index);
     return {
-        extraPaths: extraPaths.concat(additionalAutoCopletePaths),
+        extraPaths: distinctExtraPaths,
         useSnippets: false,
         caseInsensitiveCompletion: true,
         showDescriptions: true,

src/client/providers/lintProvider.ts

@@ -98,6 +98,7 @@ export class LintProvider extends vscode.Disposable {
         });
 
         this.pendingLintings.set(documentUri.fsPath, cancelToken);
+        this.outputChannel.clear();
         let promises = this.linters.map(linter => {
             if (!linter.isEnabled()) {
                 return Promise.resolve([]);