From e51c035e76d469cd638660d6f9bacf63c3b90289 Mon Sep 17 00:00:00 2001
From: "R. C. Howell" <howero@amazon.com>
Date: Fri, 20 Oct 2023 09:35:30 -0700
Subject: [PATCH] Address PR comments

---
 .../kotlin/org/partiql/ast/normalize/NormalizeTest.kt  | 10 ----------
 .../src/main/kotlin/org/partiql/planner/Env.kt         |  3 ---
 .../main/kotlin/org/partiql/planner/typer/PlanTyper.kt |  4 ++--
 .../org/partiql/types/function/FunctionSignature.kt    |  5 +++--
 4 files changed, 5 insertions(+), 17 deletions(-)
 delete mode 100644 partiql-ast/src/test/kotlin/org/partiql/ast/normalize/NormalizeTest.kt

diff --git a/partiql-ast/src/test/kotlin/org/partiql/ast/normalize/NormalizeTest.kt b/partiql-ast/src/test/kotlin/org/partiql/ast/normalize/NormalizeTest.kt
deleted file mode 100644
index 566e3669ee..0000000000
--- a/partiql-ast/src/test/kotlin/org/partiql/ast/normalize/NormalizeTest.kt
+++ /dev/null
@@ -1,10 +0,0 @@
-package org.partiql.ast.normalize
-
-import org.junit.jupiter.api.Test
-
-class NormalizeTest {
-
-    @Test
-    fun normalize() {
-    }
-}
diff --git a/partiql-planner/src/main/kotlin/org/partiql/planner/Env.kt b/partiql-planner/src/main/kotlin/org/partiql/planner/Env.kt
index e64a59a827..64d66a4052 100644
--- a/partiql-planner/src/main/kotlin/org/partiql/planner/Env.kt
+++ b/partiql-planner/src/main/kotlin/org/partiql/planner/Env.kt
@@ -11,7 +11,6 @@ import org.partiql.plan.identifierQualified
 import org.partiql.plan.identifierSymbol
 import org.partiql.planner.typer.FunctionResolver
 import org.partiql.planner.typer.Mapping
-import org.partiql.planner.typer.isNullOrMissing
 import org.partiql.planner.typer.toRuntimeType
 import org.partiql.spi.BindingCase
 import org.partiql.spi.BindingName
@@ -204,7 +203,6 @@ internal class Env(
             if (!hadMissingArg && arg.type.isMissable()) {
                 hadMissingArg = true
             }
-            arg.type.isNullOrMissing()
             FunctionParameter("arg-$i", arg.type.toRuntimeType())
         }
         val match = functionResolver.match(candidates, parameters)
@@ -227,7 +225,6 @@ internal class Env(
             if (!hadMissingArg && arg.type.isMissable()) {
                 hadMissingArg = true
             }
-            arg.type.isNullOrMissing()
             FunctionParameter("arg-$i", arg.type.toRuntimeType())
         }
         val match = functionResolver.match(candidates, parameters)
diff --git a/partiql-planner/src/main/kotlin/org/partiql/planner/typer/PlanTyper.kt b/partiql-planner/src/main/kotlin/org/partiql/planner/typer/PlanTyper.kt
index 369dcf5474..a0601f89c8 100644
--- a/partiql-planner/src/main/kotlin/org/partiql/planner/typer/PlanTyper.kt
+++ b/partiql-planner/src/main/kotlin/org/partiql/planner/typer/PlanTyper.kt
@@ -795,7 +795,7 @@ internal class PlanTyper(
             var missingArg = false
             val args = arguments.map {
                 val arg = visitRex(it, null)
-                if (arg.type == MissingType) missingArg = true
+                if (arg.type.isMissable()) missingArg = true
                 arg
             }
 
@@ -821,7 +821,7 @@ internal class PlanTyper(
 
                     // Some operators can return MISSING during runtime
                     if (match.isMissable) {
-                        type = StaticType.unionOf(type, StaticType.MISSING)
+                        type = StaticType.unionOf(type, StaticType.MISSING).flatten()
                     }
 
                     // Finally, rewrite this node
diff --git a/partiql-types/src/main/kotlin/org/partiql/types/function/FunctionSignature.kt b/partiql-types/src/main/kotlin/org/partiql/types/function/FunctionSignature.kt
index 93922d5c5b..89839c5edd 100644
--- a/partiql-types/src/main/kotlin/org/partiql/types/function/FunctionSignature.kt
+++ b/partiql-types/src/main/kotlin/org/partiql/types/function/FunctionSignature.kt
@@ -113,7 +113,8 @@ public sealed class FunctionSignature(
                 other.name != name ||
                 other.returns != returns ||
                 other.parameters.size != parameters.size ||
-                other.isDecomposable != isDecomposable
+                other.isDecomposable != isDecomposable ||
+                other.isNullable != isNullable
             ) {
                 return false
             }
@@ -131,12 +132,12 @@ public sealed class FunctionSignature(
             result = 31 * result + returns.hashCode()
             result = 31 * result + parameters.hashCode()
             result = 31 * result + isDecomposable.hashCode()
+            result = 31 * result + isNullable.hashCode()
             result = 31 * result + (description?.hashCode() ?: 0)
             return result
         }
     }
 
-
     // // Logic for writing a [FunctionSignature] using SQL `CREATE FUNCTION` syntax.
     //
     // /**