fix(linear-progress): restores progress when determinate set to true (#…

…1698)

Fixes a bug where the progress was set to 1 after determinate was toggled from false to true, regardless of what progress was set to before.

The progress value is stored in the Foundation instance, defaulting to 0 to follow #1694.

Fixes #1531

packages/mdc-linear-progress/foundation.js

@@ -46,12 +46,14 @@ export default class MDCLinearProgressFoundation extends MDCFoundation {
   init() {
     this.determinate_ = !this.adapter_.hasClass(cssClasses.INDETERMINATE_CLASS);
     this.reverse_ = this.adapter_.hasClass(cssClasses.REVERSED_CLASS);
+    this.progress_ = 0;
   }
 
   setDeterminate(isDeterminate) {
     this.determinate_ = isDeterminate;
     if (this.determinate_) {
       this.adapter_.removeClass(cssClasses.INDETERMINATE_CLASS);
+      this.setScale_(this.adapter_.getPrimaryBar(), this.progress_);
     } else {
       this.adapter_.addClass(cssClasses.INDETERMINATE_CLASS);
       this.setScale_(this.adapter_.getPrimaryBar(), 1);
@@ -60,6 +62,7 @@ export default class MDCLinearProgressFoundation extends MDCFoundation {
   }
 
   setProgress(value) {
+    this.progress_ = value;
     if (this.determinate_) {
       this.setScale_(this.adapter_.getPrimaryBar(), value);
     }

test/unit/mdc-linear-progress/foundation.test.js

@@ -63,6 +63,28 @@ test('#setDeterminate removes class', () => {
   td.verify(mockAdapter.removeClass(cssClasses.INDETERMINATE_CLASS));
 });
 
+test('#setDeterminate restores previous progress value after toggled from false to true', () => {
+  const {foundation, mockAdapter} = setupTest();
+  const primaryBar = {};
+  td.when(mockAdapter.getPrimaryBar()).thenReturn(primaryBar);
+  foundation.init();
+  foundation.setProgress(0.123);
+  foundation.setDeterminate(false);
+  foundation.setDeterminate(true);
+  td.verify(mockAdapter.setStyle(primaryBar, 'transform', 'scaleX(0.123)'), {times: 2});
+});
+
+test('#setDeterminate updates progress value set while determinate is false after determinate is true', () => {
+  const {foundation, mockAdapter} = setupTest();
+  const primaryBar = {};
+  td.when(mockAdapter.getPrimaryBar()).thenReturn(primaryBar);
+  foundation.init();
+  foundation.setDeterminate(false);
+  foundation.setProgress(0.123);
+  foundation.setDeterminate(true);
+  td.verify(mockAdapter.setStyle(primaryBar, 'transform', 'scaleX(0.123)'));
+});
+
 test('#setProgress sets transform', () => {
   const {foundation, mockAdapter} = setupTest();
   td.when(mockAdapter.hasClass(cssClasses.INDETERMINATE_CLASS)).thenReturn(false);