fix(plugins/plugin-kubectl): CurrentContext and CurrentNamespace widgets can emit console errors

part of #8155

Author: starpit

plugins/plugin-kubectl/components/src/CurrentContext.tsx

@@ -210,10 +210,8 @@ export default class CurrentContext extends React.PureComponent<Props, State> {
     if (tab) {
       const { kubectl, getTabState } = await import('@kui-shell/plugin-kubectl')
 
-      const currentContextSpec = getTabState(tab, 'context')
-      if (currentContextSpec) {
-        const currentContext = currentContextSpec.metadata.name
-
+      const currentContext = getTabState(tab, 'context')
+      if (currentContext) {
         this.setState(curState => ({
           currentContext,
           options: this.options(currentContext, curState.allContexts, kubectl),

plugins/plugin-kubectl/components/src/CurrentNamespace.tsx

@@ -88,13 +88,21 @@ export default class CurrentNamespace extends React.PureComponent<Props, State>
     try {
       const { kubectl, getCurrentDefaultNamespace } = await import('@kui-shell/plugin-kubectl')
 
+      if (this.unmounted) {
+        return
+      }
+
       const [currentNamespace, allNamespaces] = await Promise.all([
         getCurrentDefaultNamespace(tab),
         tab.REPL.qexec<string>(`${kubectl} get ns -o name`).then(_ =>
           _.split(/\n/).map(_ => _.replace(/^namespace\//, ''))
         )
       ])
 
+      if (this.unmounted) {
+        return
+      }
+
       if (currentNamespace) {
         this.setState({
           currentNamespace,
@@ -122,6 +130,9 @@ export default class CurrentNamespace extends React.PureComponent<Props, State>
     const { tab } = args
     if (tab) {
       const { getTabState } = await import('@kui-shell/plugin-kubectl')
+      if (this.unmounted) {
+        return
+      }
       const currentNamespace = getTabState(tab, 'namespace')
       if (currentNamespace) {
         this.setState({