Add array

Author: tom-andersen

firebase-firestore/src/main/java/com/google/firebase/firestore/model/Values.kt

@@ -652,16 +652,8 @@ internal object Values {
   @JvmStatic fun encodeValue(date: Date): Value = encodeValue(com.google.firebase.Timestamp((date)))
 
   @JvmStatic
-  fun encodeValue(timestamp: com.google.firebase.Timestamp): Value {
-    // Firestore backend truncates precision down to microseconds. To ensure offline mode works
-    // the same with regards to truncation, perform the truncation immediately without waiting for
-    // the backend to do that.
-    val truncatedNanoseconds: Int = timestamp.nanoseconds / 1000 * 1000
-
-    return encodeValue(
-      Timestamp.newBuilder().setSeconds(timestamp.seconds).setNanos(truncatedNanoseconds).build()
-    )
-  }
+  fun encodeValue(timestamp: com.google.firebase.Timestamp): Value =
+    encodeValue(timestamp(timestamp.seconds, timestamp.nanoseconds))
 
   @JvmStatic
   fun encodeValue(value: Timestamp): Value = Value.newBuilder().setTimestampValue(value).build()
@@ -736,6 +728,12 @@ internal object Values {
     }
 
   @JvmStatic
-  fun timestamp(seconds: Long, nanos: Int): Timestamp =
-    Timestamp.newBuilder().setSeconds(seconds).setNanos(nanos).build()
+  fun timestamp(seconds: Long, nanos: Int): Timestamp {
+    // Firestore backend truncates precision down to microseconds. To ensure offline mode works
+    // the same with regards to truncation, perform the truncation immediately without waiting for
+    // the backend to do that.
+    val truncatedNanoseconds: Int = nanos / 1000 * 1000
+
+    return Timestamp.newBuilder().setSeconds(seconds).setNanos(truncatedNanoseconds).build()
+  }
 }

firebase-firestore/src/main/java/com/google/firebase/firestore/pipeline/EvaluateResult.kt

@@ -17,6 +17,7 @@ internal sealed class EvaluateResult(val value: Value?) {
     fun long(long: Long) = EvaluateResultValue(encodeValue(long))
     fun long(int: Int) = EvaluateResultValue(encodeValue(int.toLong()))
     fun string(string: String) = EvaluateResultValue(encodeValue(string))
+    fun list(list: List<Value>) = EvaluateResultValue(encodeValue(list))
     fun timestamp(timestamp: Timestamp): EvaluateResult =
       EvaluateResultValue(encodeValue(timestamp))
     fun timestamp(seconds: Long, nanos: Int): EvaluateResult =

firebase-firestore/src/main/java/com/google/firebase/firestore/pipeline/evaluation.kt

@@ -218,6 +218,8 @@ internal val evaluateSubtract = arithmeticPrimitive(Math::subtractExact, Double:
 
 // === Array Functions ===
 
+internal val evaluateArray = variadicNullableValueFunction(EvaluateResult.Companion::list)
+
 internal val evaluateEqAny = notImplemented
 
 internal val evaluateNotEqAny = notImplemented
@@ -632,6 +634,15 @@ private inline fun variadicFunction(
   }
 }
 
+@JvmName("variadicNullableValueFunction")
+private inline fun variadicNullableValueFunction(
+  crossinline function: (List<Value>) -> EvaluateResult
+): EvaluateFunction = { params ->
+  block@{ input: MutableDocument ->
+    catch { function(params.map { p -> p(input).value ?: return@block EvaluateResultError }) }
+  }
+}
+
 @JvmName("variadicStringFunction")
 private inline fun variadicFunction(
   crossinline function: (List<String>) -> EvaluateResult

firebase-firestore/src/main/java/com/google/firebase/firestore/pipeline/expressions.kt

@@ -2601,6 +2601,26 @@ abstract class Expr internal constructor() {
     fun lte(fieldName: String, value: Any): BooleanExpr =
       BooleanExpr("lte", evaluateLte, fieldName, value)
 
+    /**
+     * Creates an expression that creates a Firestore array value from an input array.
+     *
+     * @param elements The input array to evaluate in the expression.
+     * @return A new [Expr] representing the array function.
+     */
+    @JvmStatic
+    fun array(vararg elements: Expr): Expr =
+      FunctionExpr("array", evaluateArray, elements)
+
+    /**
+     * Creates an expression that creates a Firestore array value from an input array.
+     *
+     * @param elements The input array to evaluate in the expression.
+     * @return A new [Expr] representing the array function.
+     */
+    @JvmStatic
+    fun array(elements: List<Expr>): Expr =
+      FunctionExpr("array", evaluateArray, elements.toTypedArray())
+
     /**
      * Creates an expression that concatenates an array with other arrays.
      *