Move contexts over to useXContext model

Fixes #4

src/lib/components/listbox/Listbox.svelte

@@ -34,6 +34,22 @@
     unregisterOption(id: string): void;
     select(value: unknown): void;
   };
+
+  const LISTBOX_CONTEXT_NAME = "ListboxContext";
+  export function useListboxContext(
+    component: string
+  ): Writable<StateDefinition | undefined> {
+    let context: Writable<StateDefinition | undefined> | undefined =
+      getContext(LISTBOX_CONTEXT_NAME);
+
+    if (context === undefined) {
+      throw new Error(
+        `<${component} /> is missing a parent <Listbox /> component.`
+      );
+    }
+
+    return context;
+  }
 </script>
 
 <script lang="ts">
@@ -41,7 +57,7 @@
     Focus,
     calculateActiveIndex,
   } from "$lib/utils/calculate-active-index";
-  import { createEventDispatcher, setContext } from "svelte";
+  import { createEventDispatcher, getContext, setContext } from "svelte";
   import { writable, Writable } from "svelte/store";
   import { match } from "$lib/utils/match";
   import { State, useOpenClosedProvider } from "$lib/internal/open-closed";
@@ -63,7 +79,7 @@
   let activeOptionIndex = null;
 
   let api: Writable<StateDefinition | undefined> = writable();
-  setContext("api", api);
+  setContext(LISTBOX_CONTEXT_NAME, api);
 
   let openClosedState = writable(State.Closed);
   useOpenClosedProvider(openClosedState);

src/lib/components/listbox/ListboxButton.svelte

@@ -1,10 +1,11 @@
 <script lang="ts">
   import { getContext, tick } from "svelte";
-  import { ListboxStates, StateDefinition } from "./Listbox.svelte";
+  import { ListboxStates, useListboxContext } from "./Listbox.svelte";
   import { useId } from "$lib/hooks/use-id";
   import { Keys } from "$lib/utils/keyboard";
   import { Focus } from "$lib/utils/calculate-active-index";
-  let api: SvelteStore<StateDefinition> = getContext("api");
+
+  let api = useListboxContext("ListboxButton");
   let id = `headlessui-listbox-button-${useId()}`;
   let buttonStore: SvelteStore<HTMLButtonElement> = getContext("buttonStore");
 

src/lib/components/listbox/ListboxLabel.svelte

@@ -1,8 +1,8 @@
 <script lang="ts">
   import { getContext } from "svelte";
-  import { ListboxStates, StateDefinition } from "./Listbox.svelte";
+  import { ListboxStates, useListboxContext } from "./Listbox.svelte";
   import { useId } from "$lib/hooks/use-id";
-  let api: SvelteStore<StateDefinition> = getContext("api");
+  let api = useListboxContext("ListboxLabel");
   let id = `headlessui-listbox-label-${useId()}`;
   let labelStore: SvelteStore<HTMLLabelElement> = getContext("labelStore");
 

src/lib/components/listbox/ListboxOption.svelte

@@ -1,11 +1,11 @@
 <script lang="ts">
-  import { getContext, onDestroy, onMount, tick } from "svelte";
-  import { ListboxStates, StateDefinition } from "./Listbox.svelte";
+  import { onDestroy, onMount, tick } from "svelte";
+  import { ListboxStates, useListboxContext } from "./Listbox.svelte";
   import { useId } from "$lib/hooks/use-id";
   import { Focus } from "$lib/utils/calculate-active-index";
   export let value: any;
   export let disabled = false;
-  let api: SvelteStore<StateDefinition> = getContext("api");
+  let api = useListboxContext("ListboxOption");
   let id = `headlessui-listbox-option-${useId()}`;
 
   $: active =

src/lib/components/listbox/ListboxOptions.svelte

@@ -1,12 +1,13 @@
 <script lang="ts">
   import { getContext, tick } from "svelte";
-  import { ListboxStates, StateDefinition } from "./Listbox.svelte";
+  import { ListboxStates, useListboxContext } from "./Listbox.svelte";
   import { useId } from "$lib/hooks/use-id";
   import { match } from "$lib/utils/match";
   import { Keys } from "$lib/utils/keyboard";
   import { Focus } from "$lib/utils/calculate-active-index";
   import { State, useOpenClosed } from "$lib/internal/open-closed";
-  let api: SvelteStore<StateDefinition> = getContext("api");
+
+  let api = useListboxContext("ListboxOptions");
   let id = `headlessui-listbox-options-${useId()}`;
   let optionsStore: SvelteStore<HTMLUListElement> = getContext("optionsStore");
 

src/lib/components/popover/Popover.svelte

@@ -24,6 +24,21 @@
     panelId: string;
     close(): void;
   }
+
+  const POPOVER_CONTEXT_NAME = "PopoverContext";
+  export function usePopoverContext(
+    component: string
+  ): Writable<StateDefinition | undefined> {
+    let context = getContext(POPOVER_CONTEXT_NAME) as
+      | Writable<StateDefinition | undefined>
+      | undefined;
+    if (context === undefined) {
+      throw new Error(
+        `<${component} /> is missing a parent <Popover /> component.`
+      );
+    }
+    return context;
+  }
 </script>
 
 <script lang="ts">
@@ -43,7 +58,7 @@
   let popoverState: PopoverStates = PopoverStates.Closed;
 
   let api: Writable<StateDefinition | undefined> = writable();
-  setContext("PopoverApi", api);
+  setContext(POPOVER_CONTEXT_NAME, api);
 
   let openClosedState: Writable<State> | undefined = writable();
   setContext("OpenClosed", openClosedState);

src/lib/components/popover/PopoverButton.svelte

@@ -7,19 +7,17 @@
   } from "$lib/utils/focus-management";
   import { getContext } from "svelte";
   import { writable, Writable } from "svelte/store";
-  import { PopoverStates, StateDefinition } from "./Popover.svelte";
-  import type { PopoverGroupContext } from "./PopoverGroup.svelte";
-  import type { PopoverPanelContext } from "./PopoverPanel.svelte";
+  import { PopoverStates, usePopoverContext } from "./Popover.svelte";
+  import { usePopoverGroupContext } from "./PopoverGroup.svelte";
+  import { usePopoverPanelContext } from "./PopoverPanel.svelte";
   let buttonStore: Writable<HTMLButtonElement> = getContext("PopoverButtonRef");
   export let disabled: Boolean = false;
-  let api: Writable<StateDefinition> | undefined = getContext("PopoverApi");
+  let api = usePopoverContext("PopoverButton");
 
-  const groupContext: PopoverGroupContext | undefined =
-    getContext("PopoverGroup");
-  const closeOthers = groupContext?.closeOthers;
+  let groupContext = usePopoverGroupContext();
+  let closeOthers = groupContext?.closeOthers;
 
-  let panelContext: PopoverPanelContext | undefined =
-    getContext("PopoverPanel");
+  let panelContext = usePopoverPanelContext();
   let isWithinPanel =
     panelContext === null ? false : panelContext === $api.panelId;
   if (isWithinPanel) {

src/lib/components/popover/PopoverGroup.svelte

@@ -5,11 +5,16 @@
     isFocusWithinPopoverGroup(): boolean;
     closeOthers(buttonId: string): void;
   }
+
+  const POPOVER_GROUP_CONTEXT_NAME = "PopoverGroupContext";
+  export function usePopoverGroupContext(): PopoverGroupContext | undefined {
+    return getContext(POPOVER_GROUP_CONTEXT_NAME);
+  }
 </script>
 
 <script lang="ts">
   import type { PopoverRegisterBag } from "./Popover.svelte";
-  import { setContext } from "svelte";
+  import { getContext, setContext } from "svelte";
   let groupRef: HTMLDivElement | undefined;
   let popovers: PopoverRegisterBag[] = [];
 
@@ -44,7 +49,7 @@
     }
   }
 
-  setContext("PopoverGroup", {
+  setContext(POPOVER_GROUP_CONTEXT_NAME, {
     unregisterPopover,
     registerPopover,
     isFocusWithinPopoverGroup,

src/lib/components/popover/PopoverOverlay.svelte

@@ -2,9 +2,9 @@
   import { State } from "$lib/internal/open-closed";
   import { getContext } from "svelte";
   import type { Writable } from "svelte/store";
-  import { PopoverStates, StateDefinition } from "./Popover.svelte";
+  import { PopoverStates, usePopoverContext } from "./Popover.svelte";
 
-  let api: Writable<StateDefinition> | undefined = getContext("PopoverApi");
+  let api = usePopoverContext("PopoverOverlay");
 
   let openClosedState: Writable<State> | undefined = getContext("OpenClosed");
 

src/lib/components/popover/PopoverPanel.svelte

@@ -1,5 +1,12 @@
 <script lang="ts" context="module">
   export type PopoverPanelContext = string | null;
+
+  const POPOVER_PANEL_CONTEXT_NAME = "PopoverPanelContext";
+  export function usePopoverPanelContext():
+    | StateDefinition["panelId"]
+    | undefined {
+    return getContext(POPOVER_PANEL_CONTEXT_NAME);
+  }
 </script>
 
 <script lang="ts">
@@ -13,12 +20,16 @@
   } from "$lib/utils/focus-management";
   import { getContext, setContext, onMount } from "svelte";
   import type { Writable } from "svelte/store";
-  import { PopoverStates, StateDefinition } from "./Popover.svelte";
+  import {
+    PopoverStates,
+    StateDefinition,
+    usePopoverContext,
+  } from "./Popover.svelte";
   let panelStore: SvelteStore<HTMLDivElement> = getContext("PopoverPanelRef");
   export let focus = false;
 
-  let api: Writable<StateDefinition> | undefined = getContext("PopoverApi");
-  setContext("PopoverPanelContext", $api.panelId);
+  let api = usePopoverContext("PopoverPanel");
+  setContext(POPOVER_PANEL_CONTEXT_NAME, $api.panelId);
 
   let openClosedState: Writable<State> | undefined = getContext("OpenClosed");
 

src/lib/components/switch/Switch.svelte

@@ -1,5 +1,5 @@
 <script lang="ts">
-  import type { StateDefinition } from "./SwitchGroup.svelte";
+  import { useSwitchContext } from "./SwitchGroup.svelte";
   import type { LabelContext } from "$lib/components/label/LabelProvider.svelte";
   import type { DescriptionContext } from "$lib/components/description/DescriptionProvider.svelte";
   import { useId } from "$lib/hooks/use-id";
@@ -9,7 +9,7 @@
 
   const dispatch = createEventDispatcher();
   export let checked = false;
-  let api: Writable<StateDefinition> | undefined = getContext("SwitchApi");
+  let api = useSwitchContext();
   let labelContext: Writable<LabelContext> | undefined = getContext(
     "headlessui-label-context"
   );

src/lib/components/switch/SwitchGroup.svelte

@@ -2,12 +2,19 @@
   export interface StateDefinition {
     switchStore: Writable<HTMLButtonElement | null>;
   }
+
+  const SWITCH_CONTEXT_NAME = "SwitchContext";
+  export function useSwitchContext():
+    | Writable<StateDefinition | undefined>
+    | undefined {
+    return getContext(SWITCH_CONTEXT_NAME);
+  }
 </script>
 
 <script lang="ts">
   import DescriptionProvider from "./DescriptionProvider.svelte";
   import LabelProvider from "./LabelProvider.svelte";
-  import { setContext } from "svelte";
+  import { getContext, setContext } from "svelte";
   import { Writable, writable } from "svelte/store";
 
   let switchStore: Writable<HTMLButtonElement | null> = writable(null);