Support for Arduino preferences in arduino.json. These preferences …

…are applied during any build and can be used to set custom compiler flags and defines for instance.

Addresses #975

src/arduino/arduino.ts

@@ -298,7 +298,7 @@ export class ArduinoApp {
             if (this.useArduinoCli()) {
                 args.push("--programmer", programmer)
             } else {
-                args.push("--useprogrammer", "--pref", "programmer=arduino:" + programmer)
+                args.push("--useprogrammer", "--pref", `programmer=arduino:${programmer}`);
             }
 
             args.push("--port", dc.port);
@@ -315,6 +315,14 @@ export class ArduinoApp {
             }
         }
 
+        if (dc.buildPreferences) {
+            for (const pref of dc.buildPreferences) {
+                // Note: BuildPrefSetting makes sure that each preference
+                // value consists of exactly two items (key and value).
+                args.push("--pref", `${pref[0]}=${pref[1]}`);
+            }
+        }
+
         // We always build verbosely but filter the output based on the settings
         args.push("--verbose-build");
         if (verbose) {

src/deviceContext.ts

@@ -264,6 +264,10 @@ export class DeviceContext implements IDeviceContext, vscode.Disposable {
         this.saveContext();
     }
 
+    public get buildPreferences() {
+        return this._settings.buildPreferences.value;
+    }
+
     public async initialize() {
         if (ArduinoWorkspace.rootPath && util.fileExistsSync(path.join(ArduinoWorkspace.rootPath, ARDUINO_CONFIG_FILE))) {
             vscode.window.showInformationMessage("Arduino.json already generated.");

src/deviceSettings.ts

@@ -99,6 +99,35 @@ class StrSetting extends Setting<string> {
     }
 }
 
+class BuildPrefSetting extends Setting<string[][]> {
+    public get value() {
+        return super.value;
+    }
+    public set value(value: string[][]) {
+        if (!Array.isArray(value)) {
+            super.value = super.default;
+            return;
+        }
+        if (value.length <= 0) {
+            super.value = super.default;
+            return;
+        }
+        for (const pref of value) {
+            if (!Array.isArray(pref) || pref.length !== 2) {
+                super.value = super.default;
+                return;
+            }
+            for (const i of pref) {
+                if (typeof i !== "string") {
+                    super.value = super.default;
+                    return;
+                }
+            }
+        }
+        super.value = value;
+    }
+}
+
 /**
  * This class encapsulates all device/project specific settings and
  * provides common operations on them.
@@ -114,6 +143,7 @@ export class DeviceSettings {
     public prebuild = new StrSetting();
     public postbuild = new StrSetting();
     public programmer = new StrSetting();
+    public buildPreferences = new  BuildPrefSetting();
 
     /**
      * @returns true if any of the settings values has its modified flag
@@ -129,7 +159,8 @@ export class DeviceSettings {
                this.configuration.modified ||
                this.prebuild.modified ||
                this.postbuild.modified ||
-               this.programmer.modified;
+               this.programmer.modified ||
+               this.buildPreferences.modified;
     }
     /**
      * Clear modified flags of all settings values.
@@ -145,6 +176,7 @@ export class DeviceSettings {
         this.prebuild.commit();
         this.postbuild.commit();
         this.programmer.commit();
+        this.buildPreferences.commit();
     }
     /**
      * Resets all settings values to their default values.
@@ -162,6 +194,7 @@ export class DeviceSettings {
         this.prebuild.reset();
         this.postbuild.reset();
         this.programmer.reset();
+        this.buildPreferences.reset();
         if (commit) {
             this.commit();
         }
@@ -187,6 +220,7 @@ export class DeviceSettings {
             this.prebuild.value = settings.prebuild;
             this.postbuild.value = settings.postbuild;
             this.programmer.value = settings.programmer;
+            this.buildPreferences.value = settings.buildPreferences;
             if (commit) {
                 this.commit();
             }