Part 3: Abstract pipeline_variables_form to its own component - clean up

What does this MR do and why?

Part 3 for #520831 (closed)

We are abstracting the pipeline variables form to it's own component in order to accommodate inputs work and also hide the component depending on settings.

Part 3 removes the redundant pipeline variables code

Step	MR
Set up component/query	!182376 (merged)
Build out pipeline variable form component	!182455 (merged)
Clean up and integration	[Current MR]

Screenshots or screen recordings

No UI change

How to set up and validate locally

1. Navigate to Build > Pipeline editor and enter the following into your gitlab-ci.yml

variables:
  DEPLOY_ENVIRONMENT:
    value: "staging"
    options:
      - "production"
      - "staging"
      - "canary"
    description: "The deployment target. Set to 'staging' by default."

job:
  script: echo 1

2. Navigate to -/pipelines/new and verify that your variables are output in the pipeline variables form.
3. update variables and click "New pipeline"

Related to #520831 (closed)

app/assets/javascripts/ci/pipeline_new/components/pipeline_new_form.vue

 <script>
-import {
-  GlAlert,
-  GlIcon,
-  GlButton,
-  GlCollapsibleListbox,
-  GlForm,
-  GlFormGroup,
-  GlFormInput,
-  GlFormTextarea,
-  GlLink,
-  GlSprintf,
-  GlLoadingIcon,
-} from '@gitlab/ui';
-import { GlBreakpointInstance } from '@gitlab/ui/dist/utils';
-import { uniqueId } from 'lodash';
+import { GlAlert, GlButton, GlForm, GlFormGroup, GlSprintf } from '@gitlab/ui';
 import * as Sentry from '~/sentry/sentry_browser_wrapper';
-import { fetchPolicies } from '~/lib/graphql';
-import SafeHtml from '~/vue_shared/directives/safe_html';
 import { visitUrl } from '~/lib/utils/url_utility';
 import { s__, __, n__ } from '~/locale';
 import { createAlert } from '~/alert';
-import { helpPagePath } from '~/helpers/help_page_helper';
-import {
-  IDENTITY_VERIFICATION_REQUIRED_ERROR,
-  CONFIG_VARIABLES_TIMEOUT,
-  FILE_TYPE,
-  VARIABLE_TYPE,
-} from '../constants';
+import SafeHtml from '~/vue_shared/directives/safe_html';
+import { IDENTITY_VERIFICATION_REQUIRED_ERROR } from '../constants';
 import createPipelineMutation from '../graphql/mutations/create_pipeline.mutation.graphql';
-import ciConfigVariablesQuery from '../graphql/queries/ci_config_variables.graphql';
-import filterVariables from '../utils/filter_variables';
 import RefsDropdown from './refs_dropdown.vue';
-import VariableValuesListbox from './variable_values_listbox.vue';
 import PipelineVariablesForm from './pipeline_variables_form.vue';
 
-let pollTimeout;
-export const POLLING_INTERVAL = 2000;
 const i18n = {
-  variablesDescription: s__(
-    'Pipeline|Specify variable values to be used in this run. The variables specified in the configuration file as well as %{linkStart}CI/CD settings%{linkEnd} are used by default.',
-  ),
-  overrideNoteText: s__(
-    'CiVariables|Variables specified here are %{boldStart}expanded%{boldEnd} and not %{boldStart}masked.%{boldEnd}',
-  ),
   defaultError: __('Something went wrong on our end. Please try again.'),
   refsLoadingErrorTitle: s__('Pipeline|Branches or tags could not be loaded.'),
   submitErrorTitle: s__('Pipeline|Pipeline cannot be run.'),
   configButtonTitle: s__('Pipelines|Go to the pipeline editor'),
   warningTitle: __('The form contains the following warning:'),
   maxWarningsSummary: __('%{total} warnings found: showing first %{warningsDisplayed}'),
-  removeVariableLabel: s__('CiVariables|Remove variable'),
-  learnMore: __('Learn more'),
   pipelineAriaLabel: s__('Pipeline|Variable'),
 };
 
 export default {
+  name: 'PipelineNewForm',
   i18n,
-  formElementClasses: 'gl-basis-1/4 gl-shrink-0 gl-flex-grow-0',
-  // this height value is used inline on the textarea to match the input field height
-  // it's used to prevent the overwrite if 'gl-h-7' or '!gl-h-7' were used
-  textAreaStyle: { height: '32px' },
   components: {
     GlAlert,
-    GlIcon,
     GlButton,
-    GlCollapsibleListbox,
     GlForm,
     GlFormGroup,
-    GlFormInput,
-    GlFormTextarea,
-    GlLink,
     GlSprintf,
-    GlLoadingIcon,
     PipelineVariablesForm,
     RefsDropdown,
-    VariableValuesListbox,
     PipelineAccountVerificationAlert: () =>
       import('ee_component/vue_shared/components/pipeline_account_verification_alert.vue'),
   },
@@ -141,81 +97,16 @@ export default {
         // https://gitlab.com/gitlab-org/gitlab/-/issues/287815
         fullName: this.refParam === this.defaultBranch ? `refs/heads/${this.refParam}` : undefined,
       },
-      configVariablesWithDescription: {},
-      form: {},
       errorTitle: null,
       error: null,
       pipelineVariables: [],
-      predefinedVariables: null,
       warnings: [],
       totalWarnings: 0,
       isWarningDismissed: false,
       submitted: false,
     };
   },
-  apollo: {
-    // eslint-disable-next-line @gitlab/vue-no-undef-apollo-properties
-    ciConfigVariables: {
-      fetchPolicy: fetchPolicies.NO_CACHE,
-      query: ciConfigVariablesQuery,
-      // Skip when variables already cached in `form` or feature flag is enabled
-      skip() {
-        return (
-          Object.keys(this.form).includes(this.refFullName) || this.isUsingVariablesFormComponent
-        );
-      },
-      variables() {
-        return {
-          fullPath: this.projectPath,
-          ref: this.refQueryParam,
-        };
-      },
-      update({ project }) {
-        return project?.ciConfigVariables;
-      },
-      result({ data }) {
-        this.predefinedVariables = data?.project?.ciConfigVariables;
-
-        // API cache is empty when predefinedVariables === null, so we need to
-        // poll while cache values are being populated in the backend.
-        // After CONFIG_VARIABLES_TIMEOUT ms have passed, we stop polling
-        // and populate the form regardless.
-        if (this.isFetchingCiConfigVariables && !pollTimeout) {
-          pollTimeout = setTimeout(() => {
-            this.predefinedVariables = [];
-            this.clearPolling();
-            this.populateForm();
-          }, CONFIG_VARIABLES_TIMEOUT);
-        }
-
-        if (!this.isFetchingCiConfigVariables) {
-          this.clearPolling();
-          this.populateForm();
-        }
-      },
-      error(error) {
-        Sentry.captureException(error);
-      },
-      pollInterval: POLLING_INTERVAL,
-    },
-  },
   computed: {
-    isMobile() {
-      return ['sm', 'xs'].includes(GlBreakpointInstance.getBreakpointSize());
-    },
-    removeButtonCategory() {
-      return this.isMobile ? 'secondary' : 'tertiary';
-    },
-    isFetchingCiConfigVariables() {
-      return this.predefinedVariables === null;
-    },
-    isLoading() {
-      return this.$apollo.queries.ciConfigVariables.loading || this.isFetchingCiConfigVariables;
-    },
-    isUsingVariablesFormComponent() {
-      // TODO: add feature flag
-      return true;
-    },
     overMaxWarningsLimit() {
       return this.totalWarnings > this.maxWarnings;
     },
@@ -231,0+122,0 @@
     refShortName() {
       return this.refValue.shortName;
     },
-    refFullName() {
-      return this.refValue.fullName;
-    },
-    refQueryParam() {
-      return this.refFullName || this.refShortName;
-    },
-    variables() {
-      return this.form[this.refFullName]?.variables ?? [];
-    },
-    descriptions() {
-      return this.form[this.refFullName]?.descriptions ?? {};
-    },
     identityVerificationRequiredError() {
       return this.error === IDENTITY_VERIFICATION_REQUIRED_ERROR;
     },
-    variableTypeListboxItems() {
-      return [
-        {
-          value: VARIABLE_TYPE,
-          text: s__('Pipeline|Variable'),
-        },
-        {
-          value: FILE_TYPE,
-          text: s__('Pipeline|File'),
-        },
-      ];
-    },
   },
   methods: {
-    addEmptyVariable(refValue) {
-      const { variables } = this.form[refValue];
-
-      const lastVar = variables[variables.length - 1];
-      if (lastVar?.key === '' && lastVar?.value === '') {
-        return;
-      }
-
-      variables.push({
-        uniqueId: uniqueId(`var-${refValue}`),
-        variable_type: VARIABLE_TYPE,
-        key: '',
-        value: '',
-      });
-    },
-    clearPolling() {
-      clearTimeout(pollTimeout);
-      this.$apollo.queries.ciConfigVariables.stopPolling();
-    },
-    handleVariablesUpdated(updatedVariables) {
-      this.pipelineVariables = updatedVariables;
-    },
-    populateForm() {
-      this.configVariablesWithDescription = this.predefinedVariables.reduce(
-        (accumulator, { description, key, value, valueOptions }) => {
-          if (description) {
-            accumulator.descriptions[key] = description;
-            accumulator.values[key] = value;
-            accumulator.options[key] = valueOptions;
-          }
-
-          return accumulator;
-        },
-        { descriptions: {}, values: {}, options: {} },
-      );
-
-      this.form = {
-        ...this.form,
-        [this.refFullName]: {
-          descriptions: this.configVariablesWithDescription.descriptions,
-          variables: [],
-        },
-      };
-
-      // Add default variables from yml
-      this.setVariableParams(
-        this.refFullName,
-        VARIABLE_TYPE,
-        this.configVariablesWithDescription.values,
-      );
-
-      // Add/update variables, e.g. from query string
-      if (this.variableParams) {
-        this.setVariableParams(this.refFullName, VARIABLE_TYPE, this.variableParams);
-      }
-
-      if (this.fileParams) {
-        this.setVariableParams(this.refFullName, FILE_TYPE, this.fileParams);
-      }
-
-      // Adds empty var at the end of the form
-      this.addEmptyVariable(this.refFullName);
-    },
-    // eslint-disable-next-line max-params
-    setVariable(refValue, type, key, value) {
-      const { variables } = this.form[refValue];
-
-      const variable = variables.find((v) => v.key === key);
-      if (variable) {
-        variable.type = type;
-        variable.value = value;
-      } else {
-        variables.push({
-          uniqueId: uniqueId(`var-${refValue}`),
-          key,
-          value,
-          variable_type: type,
-        });
-      }
-    },
-    setVariableAttribute(key, attribute, value) {
-      const { variables } = this.form[this.refFullName];
-      const variable = variables.find((v) => v.key === key);
-      variable[attribute] = value;
-    },
-    setVariableParams(refValue, type, paramsObj) {
-      Object.entries(paramsObj).forEach(([key, value]) => {
-        this.setVariable(refValue, type, key, value);
-      });
-    },
-    shouldShowValuesDropdown(key) {
-      return this.configVariablesWithDescription.options[key]?.length > 1;
-    },
-    removeVariable(index) {
-      this.variables.splice(index, 1);
-    },
-    canRemove(index) {
-      return index < this.variables.length - 1;
-    },
     async createPipeline() {
       this.submitted = true;
       try {
@@ -372,9 +140,7 @@ export default {
             input: {
               projectPath: this.projectPath,
               ref: this.refShortName,
-              variables: this.isUsingVariablesFormComponent
-                ? this.pipelineVariables
-                : filterVariables(this.variables),
+              variables: this.pipelineVariables,
             },
           },
         });
@@ -403,6 +169,9 @@ export default {
       // always re-enable submit button
       this.submitted = false;
     },
+    handleVariablesUpdated(updatedVariables) {
+      this.pipelineVariables = updatedVariables;
+    },
     onRefsLoadingError(error) {
       this.reportError({ title: i18n.refsLoadingErrorTitle });
 
@@ -414,22 +183,7 @@ export default {
       this.warnings = warnings;
       this.totalWarnings = totalWarnings;
     },
-    dismissError() {
-      this.error = null;
-    },
-    createListItemsFromVariableOptions(key) {
-      return this.configVariablesWithDescription.options[key].map((option) => ({
-        text: option,
-        value: option,
-      }));
-    },
-    getPipelineAriaLabel(index) {
-      return `${this.$options.i18n.pipelineAriaLabel} ${index + 1}`;
-    },
   },
-  learnMorePath: helpPagePath('ci/variables/_index', {
-    anchor: 'cicd-variable-precedence',
-  }),
 };
 </script>
 
@@ -493,7 +247,6 @@ export default {
       </gl-form-group>
 
       <pipeline-variables-form
-        v-if="isUsingVariablesFormComponent"
         :default-branch="defaultBranch"
         :file-params="fileParams"
         :is-maintainer="isMaintainer"
@@ -503,104 +256,6 @@ export default {
         :variable-params="variableParams"
         @variables-updated="handleVariablesUpdated"
       />
-      <div v-else>
-        <gl-loading-icon v-if="isLoading" class="gl-mb-5" size="md" />
-        <gl-form-group v-else :label="s__('Pipeline|Variables')">
-          <div
-            v-for="(variable, index) in variables"
-            :key="variable.uniqueId"
-            class="gl-mb-4"
-            data-testid="ci-variable-row-container"
-          >
-            <div class="gl-flex gl-flex-col gl-items-stretch gl-gap-4 md:gl-flex-row">
-              <gl-collapsible-listbox
-                :items="variableTypeListboxItems"
-                :selected="variable.variable_type"
-                block
-                fluid-width
-                :aria-label="getPipelineAriaLabel(index)"
-                :class="$options.formElementClasses"
-                data-testid="pipeline-form-ci-variable-type"
-                @select="setVariableAttribute(variable.key, 'variable_type', $event)"
-              />
-              <gl-form-input
-                v-model="variable.key"
-                :placeholder="s__('CiVariables|Input variable key')"
-                :class="$options.formElementClasses"
-                data-testid="pipeline-form-ci-variable-key-field"
-                @change="addEmptyVariable(refFullName)"
-              />
-              <variable-values-listbox
-                v-if="shouldShowValuesDropdown(variable.key)"
-                :items="createListItemsFromVariableOptions(variable.key)"
-                :selected="variable.value"
-                :class="$options.formElementClasses"
-                class="!gl-mr-0 gl-grow"
-                data-testid="pipeline-form-ci-variable-value-dropdown"
-                @select="setVariableAttribute(variable.key, 'value', $event)"
-              />
-              <gl-form-textarea
-                v-else
-                v-model="variable.value"
-                :placeholder="s__('CiVariables|Input variable value')"
-                :style="$options.textAreaStyle"
-                :no-resize="false"
-                data-testid="pipeline-form-ci-variable-value-field"
-              />
-
-              <template v-if="variables.length > 1">
-                <gl-button
-                  v-if="canRemove(index)"
-                  size="small"
-                  class="gl-shrink-0"
-                  data-testid="remove-ci-variable-row"
-                  :category="removeButtonCategory"
-                  :aria-label="$options.i18n.removeVariableLabel"
-                  @click="removeVariable(index)"
-                >
-                  <gl-icon class="!gl-mr-0" name="remove" />
-                  <span class="md:gl-hidden">{{ $options.i18n.removeVariableLabel }}</span>
-                </gl-button>
-                <gl-button
-                  v-else
-                  class="gl-invisible gl-hidden gl-shrink-0 md:gl-block"
-                  icon="remove"
-                  :aria-label="$options.i18n.removeVariableLabel"
-                />
-              </template>
-            </div>
-            <div v-if="descriptions[variable.key]" class="gl-text-subtle">
-              {{ descriptions[variable.key] }}
-            </div>
-          </div>
-
-          <template #description>
-            <gl-sprintf :message="$options.i18n.variablesDescription">
-              <template #link="{ content }">
-                <gl-link
-                  v-if="isMaintainer"
-                  :href="settingsLink"
-                  data-testid="ci-cd-settings-link"
-                  >{{ content }}</gl-link
-                >
-                <template v-else>{{ content }}</template>
-              </template>
-            </gl-sprintf>
-            <gl-link :href="$options.learnMorePath" target="_blank">{{
-              $options.i18n.learnMore
-            }}</gl-link>
-            <div class="gl-mt-4 gl-text-subtle">
-              <gl-sprintf :message="$options.i18n.overrideNoteText">
-                <template #bold="{ content }">
-                  <strong>
-                    {{ content }}
-                  </strong>
-                </template>
-              </gl-sprintf>
-            </div>
-          </template>
-        </gl-form-group>
-      </div>
 
       <div class="gl-mt-4 gl-flex">
         <gl-button