private parsePropertiesFile()

in Extension/src/LanguageServer/configurations.ts [1198:1324]
108 lines of code
34 McCabe index (conditional complexity)

    private parsePropertiesFile(): boolean {
        if (!this.propertiesFile) {
            return false;
        }
        let success: boolean = true;
        try {
            const readResults: string = fs.readFileSync(this.propertiesFile.fsPath, 'utf8');
            if (readResults === "") {
                return false; // Repros randomly when the file is initially created. The parse will get called again after the file is written.
            }

            // Try to use the same configuration as before the change.
            const newJson: ConfigurationJson = jsonc.parse(readResults);
            if (!newJson || !newJson.configurations || newJson.configurations.length === 0) {
                throw { message: localize("invalid.configuration.file", "Invalid configuration file. There must be at least one configuration present in the array.") };
            }
            if (!this.configurationIncomplete && this.configurationJson && this.configurationJson.configurations &&
                this.CurrentConfigurationIndex >= 0 && this.CurrentConfigurationIndex < this.configurationJson.configurations.length) {
                for (let i: number = 0; i < newJson.configurations.length; i++) {
                    if (newJson.configurations[i].name === this.configurationJson.configurations[this.CurrentConfigurationIndex].name) {
                        if (this.currentConfigurationIndex !== undefined) {
                            this.currentConfigurationIndex.Value = i;
                        }
                        break;
                    }
                }
            }
            this.configurationJson = newJson;
            if (this.CurrentConfigurationIndex < 0 || this.CurrentConfigurationIndex >= newJson.configurations.length) {
                const index: number | undefined = this.getConfigIndexForPlatform(newJson);
                if (this.currentConfigurationIndex !== undefined) {
                    if (index === undefined) {
                        this.currentConfigurationIndex.setDefault();
                    } else {
                        this.currentConfigurationIndex.Value = index;
                    }
                }
            }

            let dirty: boolean = false;
            for (let i: number = 0; i < this.configurationJson.configurations.length; i++) {
                const newId: string | undefined = getCustomConfigProviders().checkId(this.configurationJson.configurations[i].configurationProvider);
                if (newId !== this.configurationJson.configurations[i].configurationProvider) {
                    dirty = true;
                    this.configurationJson.configurations[i].configurationProvider = newId;
                }
            }

            // Remove disallowed variable overrides
            if (this.configurationJson.env) {
                delete this.configurationJson.env['workspaceRoot'];
                delete this.configurationJson.env['workspaceFolder'];
                delete this.configurationJson.env['workspaceFolderBasename'];
                delete this.configurationJson.env['execPath'];
                delete this.configurationJson.env['pathSeparator'];
                delete this.configurationJson.env['default'];
            }

            // Warning: There is a chance that this is incorrect in the event that the c_cpp_properties.json file was created before
            // the system includes were available.
            this.configurationIncomplete = false;

            if (this.configurationJson.version !== configVersion) {
                dirty = true;
                if (this.configurationJson.version === undefined) {
                    this.updateToVersion2();
                }

                if (this.configurationJson.version === 2) {
                    this.updateToVersion3();
                }

                if (this.configurationJson.version === 3) {
                    this.updateToVersion4();
                } else {
                    this.configurationJson.version = configVersion;
                    vscode.window.showErrorMessage(localize("unknown.properties.version", 'Unknown version number found in c_cpp_properties.json. Some features may not work as expected.'));
                }
            }

            this.configurationJson.configurations.forEach(e => {
                if ((<any>e).knownCompilers !== undefined) {
                    delete (<any>e).knownCompilers;
                    dirty = true;
                }
            });

            for (let i: number = 0; i < this.configurationJson.configurations.length; i++) {
                if ((this.configurationJson.configurations[i].compilerPathIsExplicit !== undefined)
                    || (this.configurationJson.configurations[i].cStandardIsExplicit !== undefined)
                    || (this.configurationJson.configurations[i].cppStandardIsExplicit !== undefined)
                    || (this.configurationJson.configurations[i].intelliSenseModeIsExplicit !== undefined)) {
                    dirty = true;
                    break;
                }
            }

            if (dirty) {
                try {
                    this.writeToJson();
                } catch (err) {
                    // Ignore write errors, the file may be under source control. Updated settings will only be modified in memory.
                    vscode.window.showWarningMessage(localize('update.properties.failed', 'Attempt to update "{0}" failed (do you have write access?)', this.propertiesFile.fsPath));
                    success = false;
                }
            }

            this.configurationJson.configurations.forEach(e => {
                e.compilerPathIsExplicit = e.compilerPath !== undefined;
                e.cStandardIsExplicit = e.cStandard !== undefined;
                e.cppStandardIsExplicit = e.cppStandard !== undefined;
                e.intelliSenseModeIsExplicit = e.intelliSenseMode !== undefined;
            });

        } catch (errJS) {
            const err: Error = errJS as Error;
            const failedToParse: string = localize("failed.to.parse.properties", 'Failed to parse "{0}"', this.propertiesFile.fsPath);
            vscode.window.showErrorMessage(`${failedToParse}: ${err.message}`);
            success = false;
        }

        if (success) {
            this.handleSquiggles();
        }

        return success;
    }