Merge branch 'master' into issue_19734_2

13 files changed, 721 insertions, 433 deletions

diff --git a/app/assets/javascripts/dispatcher.js.es6 b/app/assets/javascripts/dispatcher.js.es6
index 5be35cf4b41..73691f40c74 100644
--- a/app/assets/javascripts/dispatcher.js.es6
+++ b/app/assets/javascripts/dispatcher.js.es6
@@ -101,9 +101,6 @@
           new ZenMode();
           new MergedButtons();
           break;
-        case "projects:merge_requests:conflicts":
-          window.mcui = new MergeConflictResolver()
-          break;
         case 'projects:merge_requests:index':
           shortcut_handler = new ShortcutsNavigation();
           Issuable.init();
diff --git a/app/assets/javascripts/merge_conflict_data_provider.js.es6 b/app/assets/javascripts/merge_conflict_data_provider.js.es6
deleted file mode 100644
index 13ee794ba38..00000000000
--- a/app/assets/javascripts/merge_conflict_data_provider.js.es6
+++ /dev/null
@@ -1,347 +0,0 @@
-const HEAD_HEADER_TEXT    = 'HEAD//our changes';
-const ORIGIN_HEADER_TEXT  = 'origin//their changes';
-const HEAD_BUTTON_TITLE   = 'Use ours';
-const ORIGIN_BUTTON_TITLE = 'Use theirs';
-
-
-class MergeConflictDataProvider {
-
-  getInitialData() {
-    // TODO: remove reliance on jQuery and DOM state introspection
-    const diffViewType = $.cookie('diff_view');
-    const fixedLayout = $('.content-wrapper .container-fluid').hasClass('container-limited');
-
-    return {
-      isLoading      : true,
-      hasError       : false,
-      isParallel     : diffViewType === 'parallel',
-      diffViewType   : diffViewType,
-      fixedLayout    : fixedLayout,
-      isSubmitting   : false,
-      conflictsData  : {},
-      resolutionData : {}
-    }
-  }
-
-
-  decorateData(vueInstance, data) {
-    this.vueInstance = vueInstance;
-
-    if (data.type === 'error') {
-      vueInstance.hasError = true;
-      data.errorMessage = data.message;
-    }
-    else {
-      data.shortCommitSha = data.commit_sha.slice(0, 7);
-      data.commitMessage  = data.commit_message;
-
-      this.setParallelLines(data);
-      this.setInlineLines(data);
-      this.updateResolutionsData(data);
-    }
-
-    vueInstance.conflictsData = data;
-    vueInstance.isSubmitting = false;
-
-    const conflictsText = this.getConflictsCount() > 1 ? 'conflicts' : 'conflict';
-    vueInstance.conflictsData.conflictsText = conflictsText;
-  }
-
-
-  updateResolutionsData(data) {
-    const vi = this.vueInstance;
-
-    data.files.forEach( (file) => {
-      file.sections.forEach( (section) => {
-        if (section.conflict) {
-          vi.$set(`resolutionData['${section.id}']`, false);
-        }
-      });
-    });
-  }
-
-
-  setParallelLines(data) {
-    data.files.forEach( (file) => {
-      file.filePath  = this.getFilePath(file);
-      file.iconClass = `fa-${file.blob_icon}`;
-      file.blobPath  = file.blob_path;
-      file.parallelLines = [];
-      const linesObj = { left: [], right: [] };
-
-      file.sections.forEach( (section) => {
-        const { conflict, lines, id } = section;
-
-        if (conflict) {
-          linesObj.left.push(this.getOriginHeaderLine(id));
-          linesObj.right.push(this.getHeadHeaderLine(id));
-        }
-
-        lines.forEach( (line) => {
-          const { type } = line;
-
-          if (conflict) {
-            if (type === 'old') {
-              linesObj.left.push(this.getLineForParallelView(line, id, 'conflict'));
-            }
-            else if (type === 'new') {
-              linesObj.right.push(this.getLineForParallelView(line, id, 'conflict', true));
-            }
-          }
-          else {
-            const lineType = type || 'context';
-
-            linesObj.left.push (this.getLineForParallelView(line, id, lineType));
-            linesObj.right.push(this.getLineForParallelView(line, id, lineType, true));
-          }
-        });
-
-        this.checkLineLengths(linesObj);
-      });
-
-      for (let i = 0, len = linesObj.left.length; i < len; i++) {
-        file.parallelLines.push([
-          linesObj.right[i],
-          linesObj.left[i]
-        ]);
-      }
-
-    });
-  }
-
-
-  checkLineLengths(linesObj) {
-    let { left, right } = linesObj;
-
-    if (left.length !== right.length) {
-      if (left.length > right.length) {
-        const diff = left.length - right.length;
-        for (let i = 0; i < diff; i++) {
-          right.push({ lineType: 'emptyLine', richText: '' });
-        }
-      }
-      else {
-        const diff = right.length - left.length;
-        for (let i = 0; i < diff; i++) {
-          left.push({ lineType: 'emptyLine', richText: '' });
-        }
-      }
-    }
-  }
-
-
-  setInlineLines(data) {
-    data.files.forEach( (file) => {
-      file.iconClass   = `fa-${file.blob_icon}`;
-      file.blobPath    = file.blob_path;
-      file.filePath    = this.getFilePath(file);
-      file.inlineLines = []
-
-      file.sections.forEach( (section) => {
-        let currentLineType = 'new';
-        const { conflict, lines, id } = section;
-
-        if (conflict) {
-          file.inlineLines.push(this.getHeadHeaderLine(id));
-        }
-
-        lines.forEach( (line) => {
-          const { type } = line;
-
-          if ((type === 'new' || type === 'old') && currentLineType !== type) {
-            currentLineType = type;
-            file.inlineLines.push({ lineType: 'emptyLine', richText: '' });
-          }
-
-          this.decorateLineForInlineView(line, id, conflict);
-          file.inlineLines.push(line);
-        })
-
-        if (conflict) {
-          file.inlineLines.push(this.getOriginHeaderLine(id));
-        }
-      });
-    });
-  }
-
-
-  handleSelected(sectionId, selection) {
-    const vi = this.vueInstance;
-
-    vi.resolutionData[sectionId] = selection;
-    vi.conflictsData.files.forEach( (file) => {
-      file.inlineLines.forEach( (line) => {
-        if (line.id === sectionId && (line.hasConflict || line.isHeader)) {
-          this.markLine(line, selection);
-        }
-      });
-
-      file.parallelLines.forEach( (lines) => {
-        const left         = lines[0];
-        const right        = lines[1];
-        const hasSameId    = right.id === sectionId || left.id === sectionId;
-        const isLeftMatch  = left.hasConflict || left.isHeader;
-        const isRightMatch = right.hasConflict || right.isHeader;
-
-        if (hasSameId && (isLeftMatch || isRightMatch)) {
-          this.markLine(left, selection);
-          this.markLine(right, selection);
-        }
-      })
-    });
-  }
-
-
-  updateViewType(newType) {
-    const vi = this.vueInstance;
-
-    if (newType === vi.diffViewType || !(newType === 'parallel' || newType === 'inline')) {
-      return;
-    }
-
-    vi.diffViewType = newType;
-    vi.isParallel   = newType === 'parallel';
-    $.cookie('diff_view', newType, {
-      path: (gon && gon.relative_url_root) || '/'
-    });
-    $('.content-wrapper .container-fluid')
-      .toggleClass('container-limited', !vi.isParallel && vi.fixedLayout);
-  }
-
-
-  markLine(line, selection) {
-    if (selection === 'head' && line.isHead) {
-      line.isSelected   = true;
-      line.isUnselected = false;
-    }
-    else if (selection === 'origin' && line.isOrigin) {
-      line.isSelected   = true;
-      line.isUnselected = false;
-    }
-    else {
-      line.isSelected   = false;
-      line.isUnselected = true;
-    }
-  }
-
-
-  getConflictsCount() {
-    return Object.keys(this.vueInstance.resolutionData).length;
-  }
-
-
-  getResolvedCount() {
-    let  count = 0;
-    const data = this.vueInstance.resolutionData;
-
-    for (const id in data) {
-      const resolution = data[id];
-      if (resolution) {
-        count++;
-      }
-    }
-
-    return count;
-  }
-
-
-  isReadyToCommit() {
-    const { conflictsData, isSubmitting } = this.vueInstance
-    const allResolved = this.getConflictsCount() === this.getResolvedCount();
-    const hasCommitMessage = $.trim(conflictsData.commitMessage).length;
-
-    return !isSubmitting && hasCommitMessage && allResolved;
-  }
-
-
-  getCommitButtonText() {
-    const initial = 'Commit conflict resolution';
-    const inProgress = 'Committing...';
-    const vue = this.vueInstance;
-
-    return vue ? vue.isSubmitting ? inProgress : initial : initial;
-  }
-
-
-  decorateLineForInlineView(line, id, conflict) {
-    const { type }    = line;
-    line.id           = id;
-    line.hasConflict  = conflict;
-    line.isHead       = type === 'new';
-    line.isOrigin     = type === 'old';
-    line.hasMatch     = type === 'match';
-    line.richText     = line.rich_text;
-    line.isSelected   = false;
-    line.isUnselected = false;
-  }
-
-  getLineForParallelView(line, id, lineType, isHead) {
-    const { old_line, new_line, rich_text } = line;
-    const hasConflict = lineType === 'conflict';
-
-    return {
-      id,
-      lineType,
-      hasConflict,
-      isHead       : hasConflict && isHead,
-      isOrigin     : hasConflict && !isHead,
-      hasMatch     : lineType === 'match',
-      lineNumber   : isHead ? new_line : old_line,
-      section      : isHead ? 'head' : 'origin',
-      richText     : rich_text,
-      isSelected   : false,
-      isUnselected : false
-    }
-  }
-
-
-  getHeadHeaderLine(id) {
-    return {
-      id          : id,
-      richText    : HEAD_HEADER_TEXT,
-      buttonTitle : HEAD_BUTTON_TITLE,
-      type        : 'new',
-      section     : 'head',
-      isHeader    : true,
-      isHead      : true,
-      isSelected  : false,
-      isUnselected: false
-    }
-  }
-
-
-  getOriginHeaderLine(id) {
-    return {
-      id          : id,
-      richText    : ORIGIN_HEADER_TEXT,
-      buttonTitle : ORIGIN_BUTTON_TITLE,
-      type        : 'old',
-      section     : 'origin',
-      isHeader    : true,
-      isOrigin    : true,
-      isSelected  : false,
-      isUnselected: false
-    }
-  }
-
-
-  handleFailedRequest(vueInstance, data) {
-    vueInstance.hasError = true;
-    vueInstance.conflictsData.errorMessage = 'Something went wrong!';
-  }
-
-
-  getCommitData() {
-    return {
-      commit_message: this.vueInstance.conflictsData.commitMessage,
-      sections: this.vueInstance.resolutionData
-    }
-  }
-
-
-  getFilePath(file) {
-    const { old_path, new_path } = file;
-    return old_path === new_path ? new_path : `${old_path} → ${new_path}`;
-  }
-
-}
diff --git a/app/assets/javascripts/merge_conflict_resolver.js.es6 b/app/assets/javascripts/merge_conflict_resolver.js.es6
deleted file mode 100644
index 7e756433bf5..00000000000
--- a/app/assets/javascripts/merge_conflict_resolver.js.es6
+++ /dev/null
@@ -1,82 +0,0 @@
-//= require vue
-
-class MergeConflictResolver {
-
-  constructor() {
-    this.dataProvider = new MergeConflictDataProvider()
-    this.initVue()
-  }
-
-
-  initVue() {
-    const that = this;
-    this.vue   = new Vue({
-      el       : '#conflicts',
-      name     : 'MergeConflictResolver',
-      data     : this.dataProvider.getInitialData(),
-      created  : this.fetchData(),
-      computed : this.setComputedProperties(),
-      methods  : {
-        handleSelected(sectionId, selection) {
-          that.dataProvider.handleSelected(sectionId, selection);
-        },
-        handleViewTypeChange(newType) {
-          that.dataProvider.updateViewType(newType);
-        },
-        commit() {
-          that.commit();
-        }
-      }
-    })
-  }
-
-
-  setComputedProperties() {
-    const dp = this.dataProvider;
-
-    return {
-      conflictsCount() { return dp.getConflictsCount() },
-      resolvedCount() { return dp.getResolvedCount() },
-      readyToCommit() { return dp.isReadyToCommit() },
-      commitButtonText() { return dp.getCommitButtonText() }
-    }
-  }
-
-
-  fetchData() {
-    const dp = this.dataProvider;
-
-    $.get($('#conflicts').data('conflictsPath'))
-      .done((data) => {
-        dp.decorateData(this.vue, data);
-      })
-      .error((data) => {
-        dp.handleFailedRequest(this.vue, data);
-      })
-      .always(() => {
-        this.vue.isLoading = false;
-
-        this.vue.$nextTick(() => {
-          $('#conflicts .js-syntax-highlight').syntaxHighlight();
-        });
-
-        $('.content-wrapper .container-fluid')
-          .toggleClass('container-limited', !this.vue.isParallel && this.vue.fixedLayout);
-      })
-  }
-
-
-  commit() {
-    this.vue.isSubmitting = true;
-
-    $.post($('#conflicts').data('resolveConflictsPath'), this.dataProvider.getCommitData())
-      .done((data) => {
-        window.location.href = data.redirect_to;
-      })
-      .error(() => {
-        this.vue.isSubmitting = false;
-        new Flash('Something went wrong!');
-      });
-  }
-
-}
diff --git a/app/assets/javascripts/merge_conflicts/components/diff_file_editor.js.es6 b/app/assets/javascripts/merge_conflicts/components/diff_file_editor.js.es6
new file mode 100644
index 00000000000..5012bdfe997
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/components/diff_file_editor.js.es6
@@ -0,0 +1,93 @@
+((global) => {
+
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  global.mergeConflicts.diffFileEditor = Vue.extend({
+    props: {
+      file: Object,
+      onCancelDiscardConfirmation: Function,
+      onAcceptDiscardConfirmation: Function
+    },
+    data() {
+      return {
+        saved: false,
+        loading: false,
+        fileLoaded: false,
+        originalContent: '',
+      }
+    },
+    computed: {
+      classObject() {
+        return {
+          'saved': this.saved,
+          'is-loading': this.loading
+        };
+      }
+    },
+    watch: {
+      ['file.showEditor'](val) {
+        this.resetEditorContent();
+
+        if (!val || this.fileLoaded || this.loading) {
+          return;
+        }
+
+        this.loadEditor();
+      }
+    },
+    ready() {
+      if (this.file.loadEditor) {
+        this.loadEditor();
+      }
+    },
+    methods: {
+      loadEditor() {
+        this.loading = true;
+
+        $.get(this.file.content_path)
+          .done((file) => {
+            let content = this.$el.querySelector('pre');
+            let fileContent = document.createTextNode(file.content);
+
+            content.textContent = fileContent.textContent;
+
+            this.originalContent = file.content;
+            this.fileLoaded = true;
+            this.editor = ace.edit(content);
+            this.editor.$blockScrolling = Infinity; // Turn off annoying warning
+            this.editor.getSession().setMode(`ace/mode/${file.blob_ace_mode}`);
+            this.editor.on('change', () => {
+              this.saveDiffResolution();
+            });
+            this.saveDiffResolution();
+          })
+          .fail(() => {
+            new Flash('Failed to load the file, please try again.');
+          })
+          .always(() => {
+            this.loading = false;
+          });
+      },
+      saveDiffResolution() {
+        this.saved = true;
+
+        // This probably be better placed in the data provider
+        this.file.content = this.editor.getValue();
+        this.file.resolveEditChanged = this.file.content !== this.originalContent;
+        this.file.promptDiscardConfirmation = false;
+      },
+      resetEditorContent() {
+        if (this.fileLoaded) {
+          this.editor.setValue(this.originalContent, -1);
+        }
+      },
+      cancelDiscardConfirmation(file) {
+        this.onCancelDiscardConfirmation(file);
+      },
+      acceptDiscardConfirmation(file) {
+        this.onAcceptDiscardConfirmation(file);
+      }
+    }
+  });
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/components/inline_conflict_lines.js.es6 b/app/assets/javascripts/merge_conflicts/components/inline_conflict_lines.js.es6
new file mode 100644
index 00000000000..b4be1c8988d
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/components/inline_conflict_lines.js.es6
@@ -0,0 +1,12 @@
+((global) => {
+
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  global.mergeConflicts.inlineConflictLines = Vue.extend({
+    props: {
+      file: Object
+    },
+    mixins: [global.mergeConflicts.utils, global.mergeConflicts.actions],
+  });
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/components/parallel_conflict_line.js.es6 b/app/assets/javascripts/merge_conflicts/components/parallel_conflict_line.js.es6
new file mode 100644
index 00000000000..8b0a8ab2073
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/components/parallel_conflict_line.js.es6
@@ -0,0 +1,14 @@
+((global) => {
+
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  global.mergeConflicts.parallelConflictLine = Vue.extend({
+    props: {
+      file: Object,
+      line: Object
+    },
+    mixins: [global.mergeConflicts.utils, global.mergeConflicts.actions],
+    template: '#parallel-conflict-line'
+  });
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/components/parallel_conflict_lines.js.es6 b/app/assets/javascripts/merge_conflicts/components/parallel_conflict_lines.js.es6
new file mode 100644
index 00000000000..eb4cc6a9dac
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/components/parallel_conflict_lines.js.es6
@@ -0,0 +1,15 @@
+((global) => {
+
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  global.mergeConflicts.parallelConflictLines = Vue.extend({
+    props: {
+      file: Object
+    },
+    mixins: [global.mergeConflicts.utils],
+    components: {
+      'parallel-conflict-line': gl.mergeConflicts.parallelConflictLine
+    }
+  });
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/merge_conflict_service.js.es6 b/app/assets/javascripts/merge_conflicts/merge_conflict_service.js.es6
new file mode 100644
index 00000000000..da2fb8b1323
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/merge_conflict_service.js.es6
@@ -0,0 +1,30 @@
+((global) => {
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  class mergeConflictsService {
+    constructor(options) {
+      this.conflictsPath = options.conflictsPath;
+      this.resolveConflictsPath = options.resolveConflictsPath;
+    }
+
+    fetchConflictsData() {
+      return $.ajax({
+        dataType: 'json',
+        url: this.conflictsPath
+      });
+    }
+
+    submitResolveConflicts(data) {
+      return $.ajax({
+        url: this.resolveConflictsPath,
+        data: JSON.stringify(data),
+        contentType: 'application/json',
+        dataType: 'json',
+        method: 'POST'
+      });
+    }
+  };
+
+  global.mergeConflicts.mergeConflictsService = mergeConflictsService;
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/merge_conflict_store.js.es6 b/app/assets/javascripts/merge_conflicts/merge_conflict_store.js.es6
new file mode 100644
index 00000000000..5c5c65f29d4
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/merge_conflict_store.js.es6
@@ -0,0 +1,437 @@
+((global) => {
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  const diffViewType = $.cookie('diff_view');
+  const HEAD_HEADER_TEXT = 'HEAD//our changes';
+  const ORIGIN_HEADER_TEXT = 'origin//their changes';
+  const HEAD_BUTTON_TITLE = 'Use ours';
+  const ORIGIN_BUTTON_TITLE = 'Use theirs';
+  const INTERACTIVE_RESOLVE_MODE = 'interactive';
+  const EDIT_RESOLVE_MODE = 'edit';
+  const DEFAULT_RESOLVE_MODE = INTERACTIVE_RESOLVE_MODE;
+  const VIEW_TYPES = {
+    INLINE: 'inline',
+    PARALLEL: 'parallel'
+  };
+  const CONFLICT_TYPES = {
+    TEXT: 'text',
+    TEXT_EDITOR: 'text-editor'
+  };
+
+  global.mergeConflicts.mergeConflictsStore = {
+    state: {
+      isLoading: true,
+      hasError: false,
+      isSubmitting: false,
+      isParallel: diffViewType === VIEW_TYPES.PARALLEL,
+      diffViewType: diffViewType,
+      conflictsData: {}
+    },
+
+    setConflictsData(data) {
+      this.decorateFiles(data.files);
+
+      this.state.conflictsData = {
+        files: data.files,
+        commitMessage: data.commit_message,
+        sourceBranch: data.source_branch,
+        targetBranch: data.target_branch,
+        commitMessage: data.commit_message,
+        shortCommitSha: data.commit_sha.slice(0, 7),
+      };
+    },
+
+    decorateFiles(files) {
+      files.forEach((file) => {
+        file.content = '';
+        file.resolutionData = {};
+        file.promptDiscardConfirmation = false;
+        file.resolveMode = DEFAULT_RESOLVE_MODE;
+        file.filePath = this.getFilePath(file);
+        file.iconClass = `fa-${file.blob_icon}`;
+        file.blobPath = file.blob_path;
+
+        if (file.type === CONFLICT_TYPES.TEXT) {
+          file.showEditor = false;
+          file.loadEditor = false;
+
+          this.setInlineLine(file);
+          this.setParallelLine(file);
+        } else if (file.type === CONFLICT_TYPES.TEXT_EDITOR) {
+          file.showEditor = true;
+          file.loadEditor = true;
+        }
+      });
+    },
+
+    setInlineLine(file) {
+      file.inlineLines = [];
+
+      file.sections.forEach((section) => {
+        let currentLineType = 'new';
+        const { conflict, lines, id } = section;
+
+        if (conflict) {
+          file.inlineLines.push(this.getHeadHeaderLine(id));
+        }
+
+        lines.forEach((line) => {
+          const { type } = line;
+
+          if ((type === 'new' || type === 'old') && currentLineType !== type) {
+            currentLineType = type;
+            file.inlineLines.push({ lineType: 'emptyLine', richText: '' });
+          }
+
+          this.decorateLineForInlineView(line, id, conflict);
+          file.inlineLines.push(line);
+        })
+
+        if (conflict) {
+          file.inlineLines.push(this.getOriginHeaderLine(id));
+        }
+      });
+    },
+
+    setParallelLine(file) {
+      file.parallelLines = [];
+      const linesObj = { left: [], right: [] };
+
+      file.sections.forEach((section) => {
+        const { conflict, lines, id } = section;
+
+        if (conflict) {
+          linesObj.left.push(this.getOriginHeaderLine(id));
+          linesObj.right.push(this.getHeadHeaderLine(id));
+        }
+
+        lines.forEach((line) => {
+          const { type } = line;
+
+          if (conflict) {
+            if (type === 'old') {
+              linesObj.left.push(this.getLineForParallelView(line, id, 'conflict'));
+            } else if (type === 'new') {
+              linesObj.right.push(this.getLineForParallelView(line, id, 'conflict', true));
+            }
+          } else {
+            const lineType = type || 'context';
+
+            linesObj.left.push (this.getLineForParallelView(line, id, lineType));
+            linesObj.right.push(this.getLineForParallelView(line, id, lineType, true));
+          }
+        });
+
+        this.checkLineLengths(linesObj);
+      });
+
+      for (let i = 0, len = linesObj.left.length; i < len; i++) {
+        file.parallelLines.push([
+          linesObj.right[i],
+          linesObj.left[i]
+        ]);
+      }
+    },
+
+    setLoadingState(state) {
+      this.state.isLoading = state;
+    },
+
+    setErrorState(state) {
+      this.state.hasError = state;
+    },
+
+    setFailedRequest(message) {
+      this.state.hasError = true;
+      this.state.conflictsData.errorMessage = message;
+    },
+
+    getConflictsCount() {
+      if (!this.state.conflictsData.files.length) {
+        return 0;
+      }
+
+      const files = this.state.conflictsData.files;
+      let count = 0;
+
+      files.forEach((file) => {
+        if (file.type === CONFLICT_TYPES.TEXT) {
+          file.sections.forEach((section) => {
+            if (section.conflict) {
+              count++;
+            }
+          });
+        } else {
+          count++;
+        }
+      });
+
+      return count;
+    },
+
+    getConflictsCountText() {
+      const count = this.getConflictsCount();
+      const text = count ? 'conflicts' : 'conflict';
+
+      return `${count} ${text}`;
+    },
+
+    setViewType(viewType) {
+      this.state.diffView = viewType;
+      this.state.isParallel = viewType === VIEW_TYPES.PARALLEL;
+
+      $.cookie('diff_view', viewType, {
+        path: gon.relative_url_root || '/'
+      });
+    },
+
+    getHeadHeaderLine(id) {
+      return {
+        id: id,
+        richText: HEAD_HEADER_TEXT,
+        buttonTitle: HEAD_BUTTON_TITLE,
+        type: 'new',
+        section: 'head',
+        isHeader: true,
+        isHead: true,
+        isSelected: false,
+        isUnselected: false
+      };
+    },
+
+    decorateLineForInlineView(line, id, conflict) {
+      const { type } = line;
+      line.id = id;
+      line.hasConflict = conflict;
+      line.isHead = type === 'new';
+      line.isOrigin = type === 'old';
+      line.hasMatch = type === 'match';
+      line.richText = line.rich_text;
+      line.isSelected = false;
+      line.isUnselected = false;
+    },
+
+    getLineForParallelView(line, id, lineType, isHead) {
+      const { old_line, new_line, rich_text } = line;
+      const hasConflict = lineType === 'conflict';
+
+      return {
+        id,
+        lineType,
+        hasConflict,
+        isHead: hasConflict && isHead,
+        isOrigin: hasConflict && !isHead,
+        hasMatch: lineType === 'match',
+        lineNumber: isHead ? new_line : old_line,
+        section: isHead ? 'head' : 'origin',
+        richText: rich_text,
+        isSelected: false,
+        isUnselected: false
+      };
+    },
+
+    getOriginHeaderLine(id) {
+      return {
+        id: id,
+        richText: ORIGIN_HEADER_TEXT,
+        buttonTitle: ORIGIN_BUTTON_TITLE,
+        type: 'old',
+        section: 'origin',
+        isHeader: true,
+        isOrigin: true,
+        isSelected: false,
+        isUnselected: false
+      };
+    },
+
+    getFilePath(file) {
+      const { old_path, new_path } = file;
+      return old_path === new_path ? new_path : `${old_path} → ${new_path}`;
+    },
+
+    checkLineLengths(linesObj) {
+      let { left, right } = linesObj;
+
+      if (left.length !== right.length) {
+        if (left.length > right.length) {
+          const diff = left.length - right.length;
+          for (let i = 0; i < diff; i++) {
+            right.push({ lineType: 'emptyLine', richText: '' });
+          }
+        } else {
+          const diff = right.length - left.length;
+          for (let i = 0; i < diff; i++) {
+            left.push({ lineType: 'emptyLine', richText: '' });
+          }
+        }
+      }
+    },
+
+    setPromptConfirmationState(file, state) {
+      file.promptDiscardConfirmation = state;
+    },
+
+    setFileResolveMode(file, mode) {
+      if (mode === INTERACTIVE_RESOLVE_MODE) {
+        file.showEditor = false;
+      } else if (mode === EDIT_RESOLVE_MODE) {
+        // Restore Interactive mode when switching to Edit mode
+        file.showEditor = true;
+        file.loadEditor = true;
+        file.resolutionData = {};
+
+        this.restoreFileLinesState(file);
+      }
+
+      file.resolveMode = mode;
+    },
+
+    restoreFileLinesState(file) {
+      file.inlineLines.forEach((line) => {
+        if (line.hasConflict || line.isHeader) {
+          line.isSelected = false;
+          line.isUnselected = false;
+        }
+      });
+
+      file.parallelLines.forEach((lines) => {
+        const left = lines[0];
+        const right = lines[1];
+        const isLeftMatch = left.hasConflict || left.isHeader;
+        const isRightMatch = right.hasConflict || right.isHeader;
+
+        if (isLeftMatch || isRightMatch) {
+          left.isSelected = false;
+          left.isUnselected = false;
+          right.isSelected = false;
+          right.isUnselected = false;
+        }
+      });
+    },
+
+    isReadyToCommit() {
+      const files = this.state.conflictsData.files;
+      const hasCommitMessage = $.trim(this.state.conflictsData.commitMessage).length;
+      let unresolved = 0;
+
+      for (let i = 0, l = files.length; i < l; i++) {
+        let file = files[i];
+
+        if (file.resolveMode === INTERACTIVE_RESOLVE_MODE) {
+          let numberConflicts = 0;
+          let resolvedConflicts = Object.keys(file.resolutionData).length
+
+          // We only check for conflicts type 'text'
+          // since conflicts `text_editor` can´t be resolved in interactive mode
+          if (file.type === CONFLICT_TYPES.TEXT) {
+            for (let j = 0, k = file.sections.length; j < k; j++) {
+              if (file.sections[j].conflict) {
+                numberConflicts++;
+              }
+            }
+
+            if (resolvedConflicts !== numberConflicts) {
+              unresolved++;
+            }
+          }
+        } else if (file.resolveMode === EDIT_RESOLVE_MODE) {
+
+          // Unlikely to happen since switching to Edit mode saves content automatically.
+          // Checking anyway in case the save strategy changes in the future
+          if (!file.content) {
+            unresolved++;
+            continue;
+          }
+        }
+      }
+
+      return !this.state.isSubmitting && hasCommitMessage && !unresolved;
+    },
+
+    getCommitButtonText() {
+      const initial = 'Commit conflict resolution';
+      const inProgress = 'Committing...';
+
+      return this.state ? this.state.isSubmitting ? inProgress : initial : initial;
+    },
+
+    getCommitData() {
+      let commitData = {};
+
+      commitData = {
+        commit_message: this.state.conflictsData.commitMessage,
+        files: []
+      };
+
+      this.state.conflictsData.files.forEach((file) => {
+        let addFile;
+
+        addFile = {
+          old_path: file.old_path,
+          new_path: file.new_path
+        };
+
+        if (file.type === CONFLICT_TYPES.TEXT) {
+
+          // Submit only one data for type of editing
+          if (file.resolveMode === INTERACTIVE_RESOLVE_MODE) {
+            addFile.sections = file.resolutionData;
+          } else if (file.resolveMode === EDIT_RESOLVE_MODE) {
+            addFile.content = file.content;
+          }
+        } else if (file.type === CONFLICT_TYPES.TEXT_EDITOR) {
+          addFile.content = file.content;
+        }
+
+        commitData.files.push(addFile);
+      });
+
+      return commitData;
+    },
+
+    handleSelected(file, sectionId, selection) {
+      Vue.set(file.resolutionData, sectionId, selection);
+
+      file.inlineLines.forEach((line) => {
+        if (line.id === sectionId && (line.hasConflict || line.isHeader)) {
+          this.markLine(line, selection);
+        }
+      });
+
+      file.parallelLines.forEach((lines) => {
+        const left = lines[0];
+        const right = lines[1];
+        const hasSameId = right.id === sectionId || left.id === sectionId;
+        const isLeftMatch = left.hasConflict || left.isHeader;
+        const isRightMatch = right.hasConflict || right.isHeader;
+
+        if (hasSameId && (isLeftMatch || isRightMatch)) {
+          this.markLine(left, selection);
+          this.markLine(right, selection);
+        }
+      });
+    },
+
+    markLine(line, selection) {
+      if (selection === 'head' && line.isHead) {
+        line.isSelected = true;
+        line.isUnselected = false;
+      } else if (selection === 'origin' && line.isOrigin) {
+        line.isSelected = true;
+        line.isUnselected = false;
+      } else {
+        line.isSelected = false;
+        line.isUnselected = true;
+      }
+    },
+
+    setSubmitState(state) {
+      this.state.isSubmitting = state;
+    },
+
+    fileTextTypePresent() {
+      return this.state.conflictsData.files.some(f => f.type === CONFLICT_TYPES.TEXT);
+    }
+  };
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/merge_conflicts_bundle.js.es6 b/app/assets/javascripts/merge_conflicts/merge_conflicts_bundle.js.es6
new file mode 100644
index 00000000000..7fd3749b3e2
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/merge_conflicts_bundle.js.es6
@@ -0,0 +1,89 @@
+//= require vue
+//= require ./merge_conflict_store
+//= require ./merge_conflict_service
+//= require ./mixins/line_conflict_utils
+//= require ./mixins/line_conflict_actions
+//= require ./components/diff_file_editor
+//= require ./components/inline_conflict_lines
+//= require ./components/parallel_conflict_line
+//= require ./components/parallel_conflict_lines
+
+$(() => {
+  const INTERACTIVE_RESOLVE_MODE = 'interactive';
+  const conflictsEl = document.querySelector('#conflicts');
+  const mergeConflictsStore = gl.mergeConflicts.mergeConflictsStore;
+  const mergeConflictsService = new gl.mergeConflicts.mergeConflictsService({
+    conflictsPath: conflictsEl.dataset.conflictsPath,
+    resolveConflictsPath: conflictsEl.dataset.resolveConflictsPath
+  });
+
+  gl.MergeConflictsResolverApp = new Vue({
+    el: '#conflicts',
+    data: mergeConflictsStore.state,
+    components: {
+      'diff-file-editor': gl.mergeConflicts.diffFileEditor,
+      'inline-conflict-lines': gl.mergeConflicts.inlineConflictLines,
+      'parallel-conflict-lines': gl.mergeConflicts.parallelConflictLines
+    },
+    computed: {
+      conflictsCountText() { return mergeConflictsStore.getConflictsCountText() },
+      readyToCommit() { return mergeConflictsStore.isReadyToCommit() },
+      commitButtonText() { return mergeConflictsStore.getCommitButtonText() },
+      showDiffViewTypeSwitcher() { return mergeConflictsStore.fileTextTypePresent() }
+    },
+    created() {
+      mergeConflictsService
+        .fetchConflictsData()
+        .done((data) => {
+          if (data.type === 'error') {
+            mergeConflictsStore.setFailedRequest(data.message);
+          } else {
+            mergeConflictsStore.setConflictsData(data);
+          }
+        })
+        .error(() => {
+          mergeConflictsStore.setFailedRequest();
+        })
+        .always(() => {
+          mergeConflictsStore.setLoadingState(false);
+
+          this.$nextTick(() => {
+            $(conflictsEl.querySelectorAll('.js-syntax-highlight')).syntaxHighlight();
+          });
+        });
+    },
+    methods: {
+      handleViewTypeChange(viewType) {
+        mergeConflictsStore.setViewType(viewType);
+      },
+      onClickResolveModeButton(file, mode) {
+        if (mode === INTERACTIVE_RESOLVE_MODE && file.resolveEditChanged) {
+          mergeConflictsStore.setPromptConfirmationState(file, true);
+          return;
+        }
+
+        mergeConflictsStore.setFileResolveMode(file, mode);
+      },
+      acceptDiscardConfirmation(file) {
+        mergeConflictsStore.setPromptConfirmationState(file, false);
+        mergeConflictsStore.setFileResolveMode(file, INTERACTIVE_RESOLVE_MODE);
+      },
+      cancelDiscardConfirmation(file) {
+        mergeConflictsStore.setPromptConfirmationState(file, false);
+      },
+      commit() {
+        mergeConflictsStore.setSubmitState(true);
+
+        mergeConflictsService
+          .submitResolveConflicts(mergeConflictsStore.getCommitData())
+          .done((data) => {
+            window.location.href = data.redirect_to;
+          })
+          .error(() => {
+            mergeConflictsStore.setSubmitState(false);
+            new Flash('Failed to save merge conflicts resolutions. Please try again!');
+          });
+      }
+    }
+  })
+});
diff --git a/app/assets/javascripts/merge_conflicts/mixins/line_conflict_actions.js.es6 b/app/assets/javascripts/merge_conflicts/mixins/line_conflict_actions.js.es6
new file mode 100644
index 00000000000..114a2c5b305
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/mixins/line_conflict_actions.js.es6
@@ -0,0 +1,12 @@
+((global) => {
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  global.mergeConflicts.actions = {
+    methods: {
+      handleSelected(file, sectionId, selection) {
+        gl.mergeConflicts.mergeConflictsStore.handleSelected(file, sectionId, selection);
+      }
+    }
+  };
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/merge_conflicts/mixins/line_conflict_utils.js.es6 b/app/assets/javascripts/merge_conflicts/mixins/line_conflict_utils.js.es6
new file mode 100644
index 00000000000..b846a90ab2a
--- /dev/null
+++ b/app/assets/javascripts/merge_conflicts/mixins/line_conflict_utils.js.es6
@@ -0,0 +1,18 @@
+((global) => {
+  global.mergeConflicts = global.mergeConflicts || {};
+
+  global.mergeConflicts.utils = {
+    methods: {
+      lineCssClass(line) {
+        return {
+          'head': line.isHead,
+          'origin': line.isOrigin,
+          'match': line.hasMatch,
+          'selected': line.isSelected,
+          'unselected': line.isUnselected
+        };
+      }
+    }
+  };
+
+})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/username_validator.js.es6 b/app/assets/javascripts/username_validator.js.es6
index 2517f778365..bf4b2e320cd 100644
--- a/app/assets/javascripts/username_validator.js.es6
+++ b/app/assets/javascripts/username_validator.js.es6
@@ -76,7 +76,7 @@
         this.renderState();
         return $.ajax({
           type: 'GET',
-          url: `/u/${username}/exists`,
+          url: `/users/${username}/exists`,
           dataType: 'json',
           success: (res) => this.setAvailabilityState(res.exists)
         });