mergeDataOrFn() — vue Function Reference

Architecture documentation for the mergeDataOrFn() function in options.ts from the vue codebase.

Function typescript CoreInstance Reactivity calls 2 called by 1

Entity Profile

CoreInstance→ Reactivity→ mergeDataOrFn() — vue Function Reference

Dependency Diagram

graph TD
  9e1a1d94_6eb5_5e4d_50bd_7c95e856185f["mergeDataOrFn()"]
  e1b94d83_39cf_0384_0c5f_0101fd7c94ec["strats()"]
  e1b94d83_39cf_0384_0c5f_0101fd7c94ec -->|calls| 9e1a1d94_6eb5_5e4d_50bd_7c95e856185f
  e4810382_8c74_bddb_f04c_e8c3ddc8a0e7["mergeData()"]
  9e1a1d94_6eb5_5e4d_50bd_7c95e856185f -->|calls| e4810382_8c74_bddb_f04c_e8c3ddc8a0e7
  5af21a52_5316_e857_22eb_dce69bb60268["isFunction()"]
  9e1a1d94_6eb5_5e4d_50bd_7c95e856185f -->|calls| 5af21a52_5316_e857_22eb_dce69bb60268
  style 9e1a1d94_6eb5_5e4d_50bd_7c95e856185f fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

src/core/util/options.ts lines 86–126

export function mergeDataOrFn(
  parentVal: any,
  childVal: any,
  vm?: Component
): Function | null {
  if (!vm) {
    // in a Vue.extend merge, both should be functions
    if (!childVal) {
      return parentVal
    }
    if (!parentVal) {
      return childVal
    }
    // when parentVal & childVal are both present,
    // we need to return a function that returns the
    // merged result of both functions... no need to
    // check if parentVal is a function here because
    // it has to be a function to pass previous merges.
    return function mergedDataFn() {
      return mergeData(
        isFunction(childVal) ? childVal.call(this, this) : childVal,
        isFunction(parentVal) ? parentVal.call(this, this) : parentVal
      )
    }
  } else {
    return function mergedInstanceDataFn() {
      // instance merge
      const instanceData = isFunction(childVal)
        ? childVal.call(vm, vm)
        : childVal
      const defaultData = isFunction(parentVal)
        ? parentVal.call(vm, vm)
        : parentVal
      if (instanceData) {
        return mergeData(instanceData, defaultData)
      } else {
        return defaultData
      }
    }
  }
}