From 03cb84cc1476ea82cd0fb400f7a53934d1de1c21 Mon Sep 17 00:00:00 2001
From: Pete Schwamb <pete@schwamb.net>
Date: Fri, 28 Sep 2018 22:57:27 -0500
Subject: [PATCH 1/2] Refactor RC as a timeline

To provide support for a safe, accurate IRC implementation, this patch provides retrospective correction discrepancies as a timeline, which can be extended for use in integration.
---
 Common/Models/LoopSettings.swift              |   6 +-
 Loop/Base.lproj/Localizable.strings           |   4 +-
 Loop/Extensions/CollectionType+Loop.swift     |   2 +-
 Loop/Managers/DoseMath.swift                  |   2 +-
 Loop/Managers/LoopDataManager.swift           | 128 ++++++++----------
 .../PredictionTableViewController.swift       |  17 ++-
 Loop/de.lproj/Localizable.strings             |   3 -
 Loop/es.lproj/Localizable.strings             |   3 -
 Loop/fr.lproj/Localizable.strings             |   3 -
 Loop/it.lproj/Localizable.strings             |   3 -
 Loop/nb.lproj/Localizable.strings             |   3 -
 Loop/nl.lproj/Localizable.strings             |   3 -
 Loop/pl.lproj/Localizable.strings             |   3 -
 Loop/ru.lproj/Localizable.strings             |   3 -
 Loop/zh-Hans.lproj/Localizable.strings        |   3 -
 LoopUI/Extensions/CollectionType.swift        |   8 +-
 16 files changed, 79 insertions(+), 115 deletions(-)

diff --git a/Common/Models/LoopSettings.swift b/Common/Models/LoopSettings.swift
index 3e932b4813..1dcb0cd83a 100644
--- a/Common/Models/LoopSettings.swift
+++ b/Common/Models/LoopSettings.swift
@@ -23,7 +23,11 @@ struct LoopSettings {
 
     var retrospectiveCorrectionEnabled = true
 
-    let retrospectiveCorrectionInterval = TimeInterval(minutes: 30)
+    /// The interval over which to aggregate changes in glucose for retrospective correction
+    let retrospectiveCorrectionGroupingInterval = TimeInterval(minutes: 30)
+
+    /// The maximum duration over which to integrate retrospective correction changes
+    let retrospectiveCorrectionIntegrationInterval = TimeInterval(minutes: 30)
 
     /// The amount of time since a given date that data should be considered valid
     let recencyInterval = TimeInterval(minutes: 15)
diff --git a/Loop/Base.lproj/Localizable.strings b/Loop/Base.lproj/Localizable.strings
index 795ecbbb05..fdcaafce26 100644
--- a/Loop/Base.lproj/Localizable.strings
+++ b/Loop/Base.lproj/Localizable.strings
@@ -247,8 +247,8 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Issue Report";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Last comparison: %1$@ → %2$@ vs %3$@";
+/* Format string describing retrospective glucose prediction comparison. (1: Predicted glucose)(2: Actual glucose)(3: difference) */
+"prediction-description-retrospective-correction" = "Predicted: %1$@\nActual: %2$@ (%3$@)";
 
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Launches CGM app";
diff --git a/Loop/Extensions/CollectionType+Loop.swift b/Loop/Extensions/CollectionType+Loop.swift
index 2af61c8f4e..6833b7a84c 100644
--- a/Loop/Extensions/CollectionType+Loop.swift
+++ b/Loop/Extensions/CollectionType+Loop.swift
@@ -10,7 +10,7 @@ import Foundation
 import LoopKit
 
 
-public extension Sequence where Iterator.Element: TimelineValue {
+public extension Sequence where Element: TimelineValue {
     /// Returns the closest element index in the sorted sequence prior to the specified date
     ///
     /// - parameter date: The date to use in the search
diff --git a/Loop/Managers/DoseMath.swift b/Loop/Managers/DoseMath.swift
index 1192d01cc5..3366170c4a 100644
--- a/Loop/Managers/DoseMath.swift
+++ b/Loop/Managers/DoseMath.swift
@@ -201,7 +201,7 @@ private func targetGlucoseValue(percentEffectDuration: Double, minValue: Double,
 }
 
 
-extension Collection where Iterator.Element == GlucoseValue {
+extension Collection where Element == GlucoseValue {
 
     /// For a collection of glucose prediction, determine the least amount of insulin delivered at
     /// `date` to correct the predicted glucose to the middle of `correctionRange` at the time of prediction.
diff --git a/Loop/Managers/LoopDataManager.swift b/Loop/Managers/LoopDataManager.swift
index 350415712e..32a455df17 100644
--- a/Loop/Managers/LoopDataManager.swift
+++ b/Loop/Managers/LoopDataManager.swift
@@ -22,8 +22,6 @@ final class LoopDataManager {
 
     static let LoopUpdateContextKey = "com.loudnate.Loop.LoopDataManager.LoopUpdateContext"
 
-    fileprivate typealias GlucoseChange = (start: GlucoseValue, end: GlucoseValue)
-
     let carbStore: CarbStore
 
     let doseStore: DoseStore
@@ -108,7 +106,6 @@ final class LoopDataManager {
                     self.logger.info("Received notification of glucose samples changing")
 
                     self.glucoseMomentumEffect = nil
-                    self.retrospectiveGlucoseChange = nil
 
                     self.notify(forChange: .glucose)
                 }
@@ -136,7 +133,7 @@ final class LoopDataManager {
             predictedGlucose = nil
 
             // Carb data may be back-dated, so re-calculate the retrospective glucose.
-            retrospectivePredictedGlucose = nil
+            retrospectiveGlucoseDiscrepancies = nil
         }
     }
     private var insulinEffect: [GlucoseEffect]? {
@@ -155,12 +152,12 @@ final class LoopDataManager {
         }
     }
 
-    /// The change in glucose over the reflection time interval (default is 30 min)
-    fileprivate var retrospectiveGlucoseChange: GlucoseChange? {
+    private var retrospectiveGlucoseDiscrepancies: [GlucoseEffect]? {
         didSet {
-            retrospectivePredictedGlucose = nil
+            retrospectiveGlucoseDiscrepanciesSummed = retrospectiveGlucoseDiscrepancies?.combinedSums(of: settings.retrospectiveCorrectionGroupingInterval * 1.01)
         }
     }
+    private var retrospectiveGlucoseDiscrepanciesSummed: [GlucoseChange]?
 
     fileprivate var predictedGlucose: [GlucoseValue]? {
         didSet {
@@ -168,11 +165,7 @@ final class LoopDataManager {
             recommendedBolus = nil
         }
     }
-    fileprivate var retrospectivePredictedGlucose: [GlucoseValue]? {
-        didSet {
-            retrospectiveGlucoseEffect = []
-        }
-    }
+
     fileprivate var recommendedTempBasal: (recommendation: TempBasalRecommendation, date: Date)?
     fileprivate var recommendedBolus: (recommendation: BolusRecommendation, date: Date)?
 
@@ -615,19 +608,11 @@ extension LoopDataManager {
             throw LoopError.missingDataError(.glucose)
         }
 
-        let retrospectiveStart = lastGlucoseDate.addingTimeInterval(-settings.retrospectiveCorrectionInterval)
+        let retrospectiveStart = lastGlucoseDate.addingTimeInterval(-settings.retrospectiveCorrectionIntegrationInterval)
 
         let earliestEffectDate = Date(timeIntervalSinceNow: .hours(-24))
         let nextEffectDate = insulinCounteractionEffects.last?.endDate ?? earliestEffectDate
 
-        if retrospectiveGlucoseChange == nil {
-            updateGroup.enter()
-            glucoseStore.getGlucoseChange(start: retrospectiveStart) { (change) in
-                self.retrospectiveGlucoseChange = change
-                updateGroup.leave()
-            }
-        }
-
         if glucoseMomentumEffect == nil {
             updateGroup.enter()
             glucoseStore.getRecentMomentumEffect { (effects) -> Void in
@@ -638,7 +623,7 @@ extension LoopDataManager {
 
         if insulinEffect == nil {
             updateGroup.enter()
-            doseStore.getGlucoseEffects(start: min(retrospectiveStart, nextEffectDate)) { (result) -> Void in
+            doseStore.getGlucoseEffects(start: nextEffectDate) { (result) -> Void in
                 switch result {
                 case .failure(let error):
                     self.logger.error(error)
@@ -700,7 +685,7 @@ extension LoopDataManager {
 
         _ = updateGroup.wait(timeout: .distantFuture)
 
-        if retrospectivePredictedGlucose == nil {
+        if retrospectiveGlucoseDiscrepancies == nil {
             do {
                 try updateRetrospectiveGlucoseEffect()
             } catch let error {
@@ -794,7 +779,7 @@ extension LoopDataManager {
         var prediction = LoopMath.predictGlucose(startingAt: glucose, momentum: momentum, effects: effects)
 
         // Dosing requires prediction entries at least as long as the insulin model duration.
-        // If our prediciton is shorter than that, then extend it here.
+        // If our prediction is shorter than that, then extend it here.
         let finalDate = glucose.startDate.addingTimeInterval(model.effectDuration)
         if let last = prediction.last, last.startDate < finalDate {
             prediction.append(PredictedGlucoseValue(startDate: finalDate, quantity: last.quantity))
@@ -803,52 +788,39 @@ extension LoopDataManager {
         return prediction
     }
 
-    /**
-     Runs the glucose retrospective analysis using the latest effect data.
- 
-     *This method should only be called from the `dataAccessQueue`*
-     */
+    /// Generates an effect based on how large the discrepancy is between the current glucose and its predicted value.
+    ///
+    /// - Parameter effectDuration: The length of time to extend the effect
+    /// - Throws: LoopError.missingDataError
     private func updateRetrospectiveGlucoseEffect(effectDuration: TimeInterval = TimeInterval(minutes: 60)) throws {
         dispatchPrecondition(condition: .onQueue(dataAccessQueue))
-        
-        guard let carbEffect = self.carbEffect else {
-            self.retrospectivePredictedGlucose = nil
+
+        guard let carbEffects = self.carbEffect else {
+            retrospectiveGlucoseDiscrepancies = nil
+            retrospectiveGlucoseEffect = []
             throw LoopError.missingDataError(.carbEffect)
         }
 
-        guard let insulinEffect = self.insulinEffect else {
-            self.retrospectivePredictedGlucose = nil
-            throw LoopError.missingDataError(.insulinEffect)
-        }
+        retrospectiveGlucoseDiscrepancies = insulinCounteractionEffects.subtracting(carbEffects, withUniformInterval: carbStore.delta)
 
-        guard let change = retrospectiveGlucoseChange else {
-            self.retrospectivePredictedGlucose = nil
-            return  // Expected case for calibrations
+        // Our last change should be recent, otherwise clear the effects
+        guard let discrepancy = retrospectiveGlucoseDiscrepanciesSummed?.last,
+            Date().timeIntervalSince(discrepancy.endDate) <= settings.recencyInterval
+        else {
+            retrospectiveGlucoseEffect = []
+            return
         }
 
-        // Run a retrospective prediction over the duration of the recorded glucose change, using the current carb and insulin effects
-        let startDate = change.start.startDate
-        let endDate = change.end.endDate
-        let retrospectivePrediction = LoopMath.predictGlucose(startingAt: change.start, effects:
-            carbEffect.filterDateRange(startDate, endDate),
-            insulinEffect.filterDateRange(startDate, endDate)
-        )
-
-        self.retrospectivePredictedGlucose = retrospectivePrediction
-
-        guard let lastGlucose = retrospectivePrediction.last else { return }
-        let glucoseUnit = HKUnit.milligramsPerDeciliter
-        let velocityUnit = glucoseUnit.unitDivided(by: HKUnit.second())
-
-        let discrepancy = change.end.quantity.doubleValue(for: glucoseUnit) - lastGlucose.quantity.doubleValue(for: glucoseUnit) // mg/dL
+        guard let glucose = self.glucoseStore.latestGlucose else {
+            retrospectiveGlucoseEffect = []
+            throw LoopError.missingDataError(.glucose)
+        }
 
-        // Determine the interval of discrepancy, requiring a minimum of the configured interval to avoid magnifying effects from short intervals
-        let discrepancyTime = max(change.end.endDate.timeIntervalSince(change.start.endDate), settings.retrospectiveCorrectionInterval)
-        let velocity = HKQuantity(unit: velocityUnit, doubleValue: discrepancy / discrepancyTime)
-        let type = HKQuantityType.quantityType(forIdentifier: HKQuantityTypeIdentifier.bloodGlucose)!
-        let glucose = HKQuantitySample(type: type, quantity: change.end.quantity, start: change.end.startDate, end: change.end.endDate)
+        let unit = HKUnit.milligramsPerDeciliter
+        let discrepancyTime = max(discrepancy.endDate.timeIntervalSince(discrepancy.startDate), settings.retrospectiveCorrectionGroupingInterval)
+        let velocity = HKQuantity(unit: unit.unitDivided(by: .second()), doubleValue: discrepancy.quantity.doubleValue(for: unit) / discrepancyTime)
 
-        self.retrospectiveGlucoseEffect = glucose.decayEffect(atRate: velocity, for: effectDuration)
+        retrospectiveGlucoseEffect = glucose.decayEffect(atRate: velocity, for: effectDuration)
     }
 
     /// Runs the glucose prediction on the latest effect data.
@@ -1003,9 +975,9 @@ protocol LoopState {
     var recommendedTempBasal: (recommendation: TempBasalRecommendation, date: Date)? { get }
 
     var recommendedBolus: (recommendation: BolusRecommendation, date: Date)? { get }
-    
-    /// The retrospective prediction over a recent period of glucose samples
-    var retrospectivePredictedGlucose: [GlucoseValue]? { get }
+
+    /// The difference in predicted vs actual glucose over a recent period
+    var retrospectiveGlucoseDiscrepancies: [GlucoseChange]? { get }
 
     /// Calculates a new prediction from the current data using the specified effect inputs
     ///
@@ -1063,9 +1035,9 @@ extension LoopDataManager {
             return loopDataManager.recommendedBolus
         }
 
-        var retrospectivePredictedGlucose: [GlucoseValue]? {
+        var retrospectiveGlucoseDiscrepancies: [GlucoseChange]? {
             dispatchPrecondition(condition: .onQueue(loopDataManager.dataAccessQueue))
-            return loopDataManager.retrospectivePredictedGlucose
+            return loopDataManager.retrospectiveGlucoseDiscrepanciesSummed
         }
 
         func predictGlucose(using inputs: PredictionInputEffect) throws -> [GlucoseValue] {
@@ -1105,7 +1077,7 @@ extension LoopDataManager {
     func generateDiagnosticReport(_ completion: @escaping (_ report: String) -> Void) {
         getLoopState { (manager, state) in
 
-            var entries = [
+            var entries: [String] = [
                 "## LoopDataManager",
                 "settings: \(String(reflecting: manager.settings))",
 
@@ -1117,16 +1089,16 @@ extension LoopDataManager {
                 "]",
 
                 "insulinEffect: [",
-                "* GlucoseEffect(start, end, md/dL",
+                "* GlucoseEffect(start, mg/dL)",
                 (manager.insulinEffect ?? []).reduce(into: "", { (entries, entry) in
-                    entries.append("* \(entry.startDate), \(entry.endDate), \(entry.quantity.doubleValue(for: .milligramsPerDeciliter))\n")
+                    entries.append("* \(entry.startDate), \(entry.quantity.doubleValue(for: .milligramsPerDeciliter))\n")
                 }),
                 "]",
 
                 "carbEffect: [",
-                "* GlucoseEffect(start, end, md/dL",
+                "* GlucoseEffect(start, mg/dL)",
                 (manager.carbEffect ?? []).reduce(into: "", { (entries, entry) in
-                    entries.append("* \(entry.startDate), \(entry.endDate), \(entry.quantity.doubleValue(for: .milligramsPerDeciliter))\n")
+                    entries.append("* \(entry.startDate), \(entry.quantity.doubleValue(for: .milligramsPerDeciliter))\n")
                 }),
                 "]",
 
@@ -1137,13 +1109,25 @@ extension LoopDataManager {
                 }),
                 "]",
 
-                "retrospectivePredictedGlucose: \(state.retrospectivePredictedGlucose ?? [])",
+                "retrospectiveGlucoseDiscrepancies: [",
+                "* GlucoseEffect(start, mg/dL)",
+                (manager.retrospectiveGlucoseDiscrepancies ?? []).reduce(into: "", { (entries, entry) in
+                    entries.append("* \(entry.startDate), \(entry.quantity.doubleValue(for: .milligramsPerDeciliter))\n")
+                }),
+                "]",
+
+                "retrospectiveGlucoseDiscrepanciesSummed: [",
+                "* GlucoseChange(start, end, mg/dL)",
+                (manager.retrospectiveGlucoseDiscrepanciesSummed ?? []).reduce(into: "", { (entries, entry) in
+                    entries.append("* \(entry.startDate), \(entry.endDate), \(entry.quantity.doubleValue(for: .milligramsPerDeciliter))\n")
+                }),
+                "]",
+
                 "glucoseMomentumEffect: \(manager.glucoseMomentumEffect ?? [])",
                 "retrospectiveGlucoseEffect: \(manager.retrospectiveGlucoseEffect)",
                 "recommendedTempBasal: \(String(describing: state.recommendedTempBasal))",
                 "recommendedBolus: \(String(describing: state.recommendedBolus))",
                 "lastBolus: \(String(describing: manager.lastRequestedBolus))",
-                "retrospectiveGlucoseChange: \(String(describing: manager.retrospectiveGlucoseChange))",
                 "lastLoopCompleted: \(String(describing: manager.lastLoopCompleted))",
                 "lastTempBasal: \(String(describing: state.lastTempBasal))",
                 "carbsOnBoard: \(String(describing: state.carbsOnBoard))",
diff --git a/Loop/View Controllers/PredictionTableViewController.swift b/Loop/View Controllers/PredictionTableViewController.swift
index fdb529f954..14e8375b56 100644
--- a/Loop/View Controllers/PredictionTableViewController.swift	
+++ b/Loop/View Controllers/PredictionTableViewController.swift	
@@ -67,7 +67,7 @@ class PredictionTableViewController: ChartsTableViewController, IdentifiableClas
 
     // MARK: - State
 
-    private var retrospectivePredictedGlucose: [GlucoseValue]?
+    private var retrospectiveGlucoseDiscrepancies: [GlucoseChange]?
 
     private var refreshContext = RefreshContext.all
 
@@ -113,7 +113,7 @@ class PredictionTableViewController: ChartsTableViewController, IdentifiableClas
         _ = self.refreshContext.remove(.status)
         reloadGroup.enter()
         self.deviceManager.loopManager.getLoopState { (manager, state) in
-            self.retrospectivePredictedGlucose = state.retrospectivePredictedGlucose
+            self.retrospectiveGlucoseDiscrepancies = state.retrospectiveGlucoseDiscrepancies
             self.charts.setPredictedGlucoseValues(state.predictedGlucose ?? [])
 
             do {
@@ -256,15 +256,18 @@ class PredictionTableViewController: ChartsTableViewController, IdentifiableClas
         var subtitleText = input.localizedDescription(forGlucoseUnit: charts.glucoseUnit) ?? ""
 
         if input == .retrospection,
-            let startGlucose = retrospectivePredictedGlucose?.first,
-            let endGlucose = retrospectivePredictedGlucose?.last,
+            let lastDiscrepancy = retrospectiveGlucoseDiscrepancies?.last,
             let currentGlucose = self.deviceManager.loopManager.glucoseStore.latestGlucose
         {
-            let formatter = NumberFormatter.glucoseFormatter(for: charts.glucoseUnit)
-            let values = [startGlucose, endGlucose, currentGlucose].map { formatter.string(from: $0.quantity.doubleValue(for: charts.glucoseUnit)) ?? "?" }
+            let formatter = QuantityFormatter()
+            formatter.setPreferredNumberFormatter(for: charts.glucoseUnit)
+            let predicted = HKQuantity(unit: charts.glucoseUnit, doubleValue: currentGlucose.quantity.doubleValue(for: charts.glucoseUnit) - lastDiscrepancy.quantity.doubleValue(for: charts.glucoseUnit))
+            var values = [predicted, currentGlucose.quantity].map { formatter.string(from: $0, for: charts.glucoseUnit) ?? "?" }
+            formatter.numberFormatter.positivePrefix = formatter.numberFormatter.plusSign
+            values.append(formatter.string(from: lastDiscrepancy.quantity, for: charts.glucoseUnit) ?? "?" )
 
             let retro = String(
-                format: NSLocalizedString("Last comparison: %1$@ → %2$@ vs %3$@", comment: "Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose)"),
+                format: NSLocalizedString("prediction-description-retrospective-correction", comment: "Format string describing retrospective glucose prediction comparison. (1: Predicted glucose)(2: Actual glucose)(3: difference)"),
                 values[0], values[1], values[2]
             )
 
diff --git a/Loop/de.lproj/Localizable.strings b/Loop/de.lproj/Localizable.strings
index b3a0814f9f..73db5816ed 100644
--- a/Loop/de.lproj/Localizable.strings
+++ b/Loop/de.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Problembericht";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Letzter Vergleich: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Startet die CGM-App";
 
diff --git a/Loop/es.lproj/Localizable.strings b/Loop/es.lproj/Localizable.strings
index 1b3fdb51a6..313e2b5464 100644
--- a/Loop/es.lproj/Localizable.strings
+++ b/Loop/es.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Informe de Errores";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Última comparación: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Lanza app MCG";
 
diff --git a/Loop/fr.lproj/Localizable.strings b/Loop/fr.lproj/Localizable.strings
index 56d14c322d..cf32d7c90c 100644
--- a/Loop/fr.lproj/Localizable.strings
+++ b/Loop/fr.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Editer rapport";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Dernière comparaison: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Lance Application CGM";
 
diff --git a/Loop/it.lproj/Localizable.strings b/Loop/it.lproj/Localizable.strings
index 7075cf1edf..83e6ce0170 100644
--- a/Loop/it.lproj/Localizable.strings
+++ b/Loop/it.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Segnalazione";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Ultimo confronto: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Avvia CGM app";
 
diff --git a/Loop/nb.lproj/Localizable.strings b/Loop/nb.lproj/Localizable.strings
index bb9d1069bc..0327aa145f 100644
--- a/Loop/nb.lproj/Localizable.strings
+++ b/Loop/nb.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Hendelsesrapport";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Siste sammenligning: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Starter CGM app";
 
diff --git a/Loop/nl.lproj/Localizable.strings b/Loop/nl.lproj/Localizable.strings
index 8fd598f9aa..aa7fe74b94 100644
--- a/Loop/nl.lproj/Localizable.strings
+++ b/Loop/nl.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Incidenten rapportage";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Laatste vergelijking: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Start de CGM app op";
 
diff --git a/Loop/pl.lproj/Localizable.strings b/Loop/pl.lproj/Localizable.strings
index 9a6383adea..b77dd05ba1 100644
--- a/Loop/pl.lproj/Localizable.strings
+++ b/Loop/pl.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Zgłaszanie błędów";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Ostatnie porównanie: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Uruchamia aplikację CGM";
 
diff --git a/Loop/ru.lproj/Localizable.strings b/Loop/ru.lproj/Localizable.strings
index cc41fc09fb..c23a1eb427 100644
--- a/Loop/ru.lproj/Localizable.strings
+++ b/Loop/ru.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "Сообщить об ошибе";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "Недавнее сравнение %1$@ → %2$@ и %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "Запускает приложение  непрерывного мониторинга CGM";
 
diff --git a/Loop/zh-Hans.lproj/Localizable.strings b/Loop/zh-Hans.lproj/Localizable.strings
index 9da1ff3b01..0e79f3540a 100644
--- a/Loop/zh-Hans.lproj/Localizable.strings
+++ b/Loop/zh-Hans.lproj/Localizable.strings
@@ -247,9 +247,6 @@
 /* The title text for the issue report cell */
 "Issue Report" = "反馈问题";
 
-/* Format string describing retrospective glucose prediction comparison. (1: Previous glucose)(2: Predicted glucose)(3: Actual glucose) */
-"Last comparison: %1$@ → %2$@ vs %3$@" = "的最后一次对比: %1$@ → %2$@ vs %3$@";
-
 /* Glucose HUD accessibility hint */
 "Launches CGM app" = "启动CGM软件";
 
diff --git a/LoopUI/Extensions/CollectionType.swift b/LoopUI/Extensions/CollectionType.swift
index cb0444941c..c6b80f181e 100644
--- a/LoopUI/Extensions/CollectionType.swift
+++ b/LoopUI/Extensions/CollectionType.swift
@@ -9,7 +9,7 @@
 import Foundation
 
 
-extension BidirectionalCollection where Index: Strideable, Iterator.Element: Comparable, Index.Stride == Int {
+extension BidirectionalCollection where Index: Strideable, Element: Comparable, Index.Stride == Int {
 
     /**
      Returns the insertion index of a new value in a sorted collection
@@ -20,7 +20,7 @@ extension BidirectionalCollection where Index: Strideable, Iterator.Element: Com
 
      - returns: The appropriate insertion index, between `startIndex` and `endIndex`
      */
-    func findInsertionIndex(for value: Iterator.Element) -> Index {
+    func findInsertionIndex(for value: Element) -> Index {
         var low = startIndex
         var high = endIndex
 
@@ -39,7 +39,7 @@ extension BidirectionalCollection where Index: Strideable, Iterator.Element: Com
 }
 
 
-extension BidirectionalCollection where Index: Strideable, Iterator.Element: Strideable, Index.Stride == Int {
+extension BidirectionalCollection where Index: Strideable, Element: Strideable, Index.Stride == Int {
     /**
      Returns the index of the closest element to a specified value in a sorted collection
 
@@ -47,7 +47,7 @@ extension BidirectionalCollection where Index: Strideable, Iterator.Element: Str
 
      - returns: The index of the closest element, or nil if the collection is empty
      */
-    func findClosestElementIndex(matching value: Iterator.Element) -> Index? {
+    func findClosestElementIndex(matching value: Element) -> Index? {
         let upperBound = findInsertionIndex(for: value)
 
         if upperBound == startIndex {

From 542219ac1b2c3687a1a38c3397951a08e14f8366 Mon Sep 17 00:00:00 2001
From: Pete Schwamb <pete@schwamb.net>
Date: Sat, 29 Sep 2018 00:41:53 -0500
Subject: [PATCH 2/2] Bump LoopKit dev revision

---
 Cartfile.resolved | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Cartfile.resolved b/Cartfile.resolved
index 1676b87ad7..fc3216c8a5 100644
--- a/Cartfile.resolved
+++ b/Cartfile.resolved
@@ -1,7 +1,7 @@
 github "LoopKit/Amplitude-iOS" "2137d5fd44bf630ed33e1e72d7af6d8f8612f270"
 github "LoopKit/CGMBLEKit" "97433c2c546b50268bbfe2e1a42cb377c6066e78"
 github "LoopKit/G4ShareSpy" "47931f1ee70f1081db6eebf3a68bb8f4146e5fca"
-github "LoopKit/LoopKit" "8c553f7bd03c2032b146e4a52d58d527a4285c15"
+github "LoopKit/LoopKit" "f130260f76d5e58a5984045484331a363e1b7080"
 github "LoopKit/dexcom-share-client-swift" "f0125aed8960586a9473dca02d17b3e5969558ac"
 github "i-schuetz/SwiftCharts" "0.6.2"
 github "ps2/rileylink_ios" "49a43189c1606875d27133589c6d6b92fbd3a0a1"