full test suite for accelerometer API, using assert. Each test tested…

… individually but not all together bc assert not currently running on Tessel

test/apiTest.js

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+var assert = require('assert');
+var async = require('async');
+
+var tessel = require('tessel');
+var startTime = new Date(milliseconds);
+var accel = require('../').use(tessel.port[process.argv[2] || 'A']);
+var requireTime = new Date(milliseconds);
+
+// Make sure accel-mma84 requires in a reasonable amount of time
+assert(requireTime - startTime < 500, 'timed out requiring accel-mma84');
+
+
+//***Events***//
+//ready
+  // It calls ready within a reasonable amount of time
+  accel.on('ready', function() {
+    var readyTime = new Date(milliseconds);
+    assert(readyTime - requireTime < 500, 'timed out waiting for ready event');
+//data
+    // It gets data within a reasonable amount of time
+    var firstData = true;
+    accel.on('data', function(data) {
+      if(firstData) {
+        var dataTime = new Date(milliseconds);
+        assert(dataTime - readyTime < 300, 'timed out waiting for initial data');
+        // Check the data to make sure it's valid
+        checkValidAccelData(data);
+        firstData = false;
+      }
+    });
+  });
+
+//error
+  // Fail if we get an error
+  accel.on('error', function (err) {
+    assert(false, 'error caught: ' + err);
+  });
+
+//***Methods***//
+//availableOutputRates
+var rates = accel.availableOutputRates();
+// Return value has a length
+assert(rates.length > 0, 'returned value from availableOutputRates has no length');
+// The things in the returned array are numbers
+rates.forEach(function (val) {
+  assert((typeof val) == 'number', 'value ' + val + 'is not a number');
+});
+
+//availableScaleRanges()
+var rates = accel.availableOutputRates();
+// Return value has a length
+assert(rates.length > 0, 'returned value from availableScaleRanges has no length');
+// The things in the returned array are numbers
+rates.forEach(function (val) {
+  assert((typeof val) == 'number', 'value ' + val + 'is not a number');
+});
+
+//enableDataInterrupts
+var timeToWait = 1100;
+var counter = 0;
+// Enable initially
+accel.enableDataInterrupts(true, function () {
+  setTimeout(function () {
+    // Disable
+    accel.enableDataInterrupts(false, function () {
+      counter++;
+      setTimeout(function () {
+        // Enable
+        accel.enableDataInterrupts(true, function () {
+          counter++;
+        });
+      }, timeToWait);
+    });
+  }, timeToWait);
+});
+// Collect data
+var collector = {0:0, 1:0, 2:0}; // 0 enabled, 1 disabled, 2 re-enabled
+accel.on('data', function (data) {
+  collector[counter] ++;
+});
+// Stop listening once test is complete
+setTimeout(function () {
+  accel.removeAllListeners('data');
+  // Evaluate results
+  assert(collector[0] > 2, 'no data emitted initially');
+  assert(collector[1] < 2, 'data continues to be emitted after data interrupts disabled');
+  assert(collector[2] > 2, 'data not emitted even after data interrupts re-enabled');
+}, timeToWait * 3);
+
+//getAcceleration
+accel.getAcceleration(function (err, data) {
+  // Make sure there's no error
+  assert(!err, 'error in getAcceleration');
+  // Check the data to make sure it's valid
+  checkValidAccelData(data);  
+});
+
+//setOutputRate
+// Check for all available output rates
+async.eachSeries(accel.availableOutputRates(), function (rate, callback) {
+  // Function completes in a reasonable amount of time
+  var aboutToSet = new Date(milliseconds);
+  accel.setOutputRate(rate, function (err) {
+    var justSet = new Date(milliseconds);
+    assert(justSet - aboutToSet < 900, 'timed out setting output rate ' + rate);
+    // New output rate matches the requested output rate (10% tolerance)
+    var count = 0;
+    var thisTime;
+    var lastTime;
+    var freq;
+    accel.on('data', function (data) {
+      thisTime = new Date(milliseconds);
+      if(count) { // Check the first few data points
+        freq = 1000/(thisTime - lastTime);
+        if(rate > 12.5) {
+          assert(freq > 11, 'rate ' + rate + 'Hz failed, measured frequency ' + freq + 'Hz'); // WORKAROUND: this is sucky but on current firmware this is about as fast as it can go
+        } else {
+          assert(freq < (rate * 1.1) && freq > (rate * 0.9), 'rate ' + rate + 'Hz failed, measured frequency ' + freq + 'Hz');
+        }
+      }
+      lastTime = thisTime;
+      count ++;
+      if(count > 6) {
+        accel.removeAllListeners('data');
+        callback();
+      }
+    });
+  });
+});
+
+//setScaleRange
+// Check for all available scale ranges
+var ranges = accel.availableScaleRanges();
+var collector = {};
+async.eachSeries(accel.availableScaleRanges(), function (range, callback) {
+  // Function completes in a reasonable amount of time
+  var aboutToSet = new Date(milliseconds);
+  accel.setScaleRange(range, function (err) {
+    var justSet = new Date(milliseconds);
+    assert(justSet - aboutToSet < 300, 'timed out setting output rate ' + range);
+    accel.getAcceleration(function (err, data) {
+      collector[range] = data;
+      callback();
+    });
+  });
+}, function () {
+  // Make sure the different settings are proportionally accurate
+  baseline = ranges[0];
+  var proportion;
+  ranges.forEach(function (range) {
+    proportion = range / baseline;
+    collector[baseline].forEach(function (datum, index) {
+      assert(collector[range][index] / datum == proportion, 'error setting range to ' + range + 'Gs; unexpected output');
+    });
+  });
+});
+
+function checkValidAccelData(dataArray) {
+  // Data has length 3
+  assert(dataArray.length == 3, 'there should be three values in an accelerometer reading');
+  // The three things in data are numbers
+  dataArray.forEach(function (val) {
+    assert((typeof val) == 'number', 'value ' + val + 'should be a number');
+  });
+}