From 95e9c6cb2493f206fd5781a12ad5feb8921fb74b Mon Sep 17 00:00:00 2001
From: Dominik Haentsch <dominik.haentsch@gmail.com>
Date: Mon, 26 Feb 2024 13:53:32 +0100
Subject: [PATCH] feat: optional handlesNull attribute for lenses

---
 src/components/ui/Select/Select.tsx |  2 +-
 src/lenses/LensFactory.tsx          | 29 ++++++++++++-----------------
 src/types/lenses.ts                 |  1 +
 3 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/src/components/ui/Select/Select.tsx b/src/components/ui/Select/Select.tsx
index 42808e1d..5fe494dd 100644
--- a/src/components/ui/Select/Select.tsx
+++ b/src/components/ui/Select/Select.tsx
@@ -23,7 +23,7 @@ interface SelectProps<T extends Value> {
 }
 
 function defaultLabel<T extends Value>(v?: T) {
-    return v?.toString() || 'None';
+    return v?.toString() ?? 'None';
 }
 
 function Select<T extends Value>({
diff --git a/src/lenses/LensFactory.tsx b/src/lenses/LensFactory.tsx
index f8117d4f..a2171da3 100644
--- a/src/lenses/LensFactory.tsx
+++ b/src/lenses/LensFactory.tsx
@@ -104,27 +104,22 @@ const LensFactory: FunctionComponent<Props> = ({
     if (!isLensCompatible(LensComponent, types, allEditable))
         return <Info>Incompatible View ({view})</Info>;
 
-    const context = { settings, onChangeSettings, sharedState, setSharedState };
-
-    const allValuesAreNull = values.every(_.isNull);
+    if (!LensComponent?.handlesNull && values.every(_.isNull)) return <None />;
 
+    const context = { settings, onChangeSettings, sharedState, setSharedState };
     return (
         <LensContext.Provider value={context}>
             <ErrorBoundary fallbackRender={fallbackRenderer}>
-                {allValuesAreNull ? (
-                    <None />
-                ) : (
-                    <LensComponent
-                        url={urls[0]}
-                        urls={urls}
-                        value={values[0]}
-                        values={values}
-                        column={columns[0]}
-                        columns={columns}
-                        rowIndex={rowIndex}
-                        syncKey={syncKey}
-                    />
-                )}
+                <LensComponent
+                    url={urls[0]}
+                    urls={urls}
+                    value={values[0]}
+                    values={values}
+                    column={columns[0]}
+                    columns={columns}
+                    rowIndex={rowIndex}
+                    syncKey={syncKey}
+                />
             </ErrorBoundary>
         </LensContext.Provider>
     );
diff --git a/src/types/lenses.ts b/src/types/lenses.ts
index e6f65388..303bafdb 100644
--- a/src/types/lenses.ts
+++ b/src/types/lenses.ts
@@ -30,6 +30,7 @@ interface LensAttributes {
         selectedColumns: DataColumn[]
     ) => DataColumn[];
     isSatisfied?: (columns: DataColumn[]) => boolean;
+    handlesNull?: boolean;
 }
 
 export type Lens<T = unknown> = React.FunctionComponent<LensProps<T>> & LensAttributes;