reducers: Make LINK_CLICK finalize but not close

... the interaction.

Following on from Iccba3c4c, LINK_CLICK shouldn't be considered the end
of an interaction because the link or preview can still be abandoned by
the user. Unlike ABANDON_END and LINK_DWELL, therefore, LINK_CLICK
musn't destroy the interaction but indicate that no more events should
be enqueued for the interaction.

More concretely, if the user has clicked the link or the preview, then
a "dwelledButAbandoned" or "dismissed" event shouldn't be logged.

Changes:
* Distinguish between "finalizing" and "closing" an interaction, where
  the latter is the current behavior of ABANDON_END, LINK_DWELL, and
  LINK_CLICK, in the eventLogging reducer and associated tests.
* If the interaction is finalized, then either the "dwelledButAbandoned"
  or "dismissed" events shouldn't be logged.

Bug: T162924
Change-Id: I09d8776da992053f89a77508e29a7cde3cfeeac6

src/reducers/eventLogging.js

@@ -33,16 +33,26 @@ function getBaseData( bootAction ) {
  * Creates an event that, when mixed into the base data (see `getBaseData`),
  * represents the user abandoning a link or preview.
  *
+ * Since the event should be logged when the user has either abandoned a link or
+ * dwelled on a different link, we refer to these events as "closing" events as
+ * the link interaction has finished and a new one will be created later.
+ *
+ * If the link interaction is finalized, i.e. if an event has already been
+ * logged for the link interaction, then no closing event is created.
+ *
  * @param {Object} interaction
- * @param {Number} endTimestamp
+ * @return {Object|undefined}
- * @return {Object}
  */
-function createAbandonEvent( interaction ) {
+function createClosingEvent( interaction ) {
 	var result = {
 		linkInteractionToken: interaction.token,
 		totalInteractionTime: Math.round( interaction.finished - interaction.started )
 	};
 
+	if ( interaction.finalized ) {
+		return undefined;
+	}
+
 	// Has the preview been shown? If so, then, in the context of the
 	// instrumentation, then the preview has been dismissed by the user
 	// rather than the user has abandoned the link.
@@ -166,7 +176,7 @@ module.exports = function ( state, action ) {
 
 				// Was the user interacting with another link? If so, then log the
 				// abandoned event.
-				event: state.interaction ? createAbandonEvent( state.interaction ) : undefined
+				event: state.interaction ? createClosingEvent( state.interaction ) : undefined
 			} );
 
 		case actionTypes.PREVIEW_DWELL:
@@ -178,7 +188,9 @@ module.exports = function ( state, action ) {
 
 		case actionTypes.LINK_CLICK:
 			return nextState( state, {
-				interaction: undefined,
+				interaction: {
+					finalized: true
+				},
 				event: {
 					action: 'opened',
 					linkInteractionToken: state.interaction.token,
@@ -199,7 +211,7 @@ module.exports = function ( state, action ) {
 			if ( !state.interaction.isUserDwelling ) {
 				return nextState( state, {
 					interaction: undefined,
-					event: createAbandonEvent( state.interaction )
+					event: createClosingEvent( state.interaction )
 				} );
 			}
 

tests/node-qunit/reducers/eventLogging.test.js

@@ -221,15 +221,16 @@ QUnit.test( 'LINK_DWELL doesn\'t start a new interaction under certain condition
 QUnit.test(
 	'LINK_DWELL should enqueue a "dismissed" or "dwelledButAbandoned" event under certain conditions',
 	function ( assert ) {
-		var state,
+		var token = '0987654321',
-			now = Date.now();
+			now = Date.now(),
+			state;
 
 		// Read: The user dwells on link A, abandons it, and dwells on link B fewer
 		// than 300 ms after (before the ABANDON_END action is reduced).
 		state = eventLogging( undefined, {
 			type: 'LINK_DWELL',
 			el: this.link,
-			token: '0987654321',
+			token: token,
 			timestamp: now
 		} );
 
@@ -253,6 +254,33 @@ QUnit.test(
 				action: 'dwelledButAbandoned'
 			}
 		);
+
+		// ---
+
+		state = eventLogging( undefined, {
+			type: 'LINK_DWELL',
+			el: this.link,
+			token: token,
+			timestamp: now
+		} );
+
+		state = eventLogging( state, {
+			type: 'LINK_CLICK',
+			el: this.link
+		} );
+
+		state = eventLogging( state, {
+			type: 'LINK_DWELL',
+			el: $( '<a>' ),
+			token: 'banana',
+			timestamp: now + 500
+		} );
+
+		assert.strictEqual(
+			state.event,
+			undefined,
+			'It shouldn\'t enqueue either event if the interaction is finalized.'
+		);
 	}
 );
 
@@ -286,8 +314,8 @@ QUnit.test( 'LINK_CLICK should enqueue an "opened" event', function ( assert ) {
 	);
 
 	assert.strictEqual(
-		state.interaction,
+		state.interaction.finalized,
-		undefined,
+		true,
 		'It should finalize the interaction.'
 	);
 } );
@@ -504,7 +532,7 @@ QUnit.test( 'ABANDON_END should enqueue an event', function ( assert ) {
 	assert.strictEqual(
 		state.interaction,
 		undefined,
-		'It should finalize the interaction.'
+		'It should close the interaction.'
 	);
 
 	// ---
@@ -541,14 +569,16 @@ QUnit.test( 'ABANDON_END should enqueue an event', function ( assert ) {
 } );
 
 QUnit.test( 'ABANDON_END doesn\'t enqueue an event under certain conditions', function ( assert ) {
-	var dwelledState,
+	var token = '0987654321',
+		now = Date.now(),
+		dwelledState,
 		state;
 
 	dwelledState = eventLogging( undefined, {
 		type: 'LINK_DWELL',
 		el: this.link,
-		token: '0987654321',
+		token: token,
-		timestamp: Date.now()
+		timestamp: now
 	} );
 
 	state = eventLogging( dwelledState, {
@@ -566,12 +596,35 @@ QUnit.test( 'ABANDON_END doesn\'t enqueue an event under certain conditions', fu
 
 	state = eventLogging( dwelledState, {
 		type: 'ABANDON_END',
-		token: '0987654321'
+		token: token
 	} );
 
 	assert.strictEqual(
 		state.event,
 		undefined,
-		'It shouldn\'t enqueue an event if the use is dwelling on the preview or the link.'
+		'It shouldn\'t enqueue an event if the user is dwelling on the preview or the link.'
+	);
+
+	// ---
+
+	state = eventLogging( dwelledState, {
+		type: 'LINK_CLICK',
+		timestamp: now + 500
+	} );
+
+	state = eventLogging( state, {
+		type: 'ABANDON_START',
+		timestamp: now + 700
+	} );
+
+	state = eventLogging( state, {
+		type: 'ABANDON_END',
+		timestamp: now + 1000 // ABANDON_END_DELAY is 300 ms.
+	} );
+
+	assert.strictEqual(
+		state.event,
+		undefined,
+		'It shouldn\'t enqueue an event if the interaction is finalized.'
 	);
 } );