PBT 2021의 도래 - Day 20 - 솔루션

속성 1: 선형 트렁크를 구축해야 합니다.

for any requested size of tree n
it should render a tree having a linear trunk

it("should build a linear trunc", () => {
  fc.assert(
    fc.property(fc.integer({ min: 1, max: 1000 }), (n) => {
      // Arrange / Act
      const tree = drawTree(n);

      // Assert
      // Remove all the leaves from the tree to only keep the trunk
      const treeWithoutLeaves = tree
        .split("\n")
        .map((level) => level.replace(/[()]/g, " ").trimRight());
      for (const level of treeWithoutLeaves) {
        expect(level.trimLeft()).toEqual("^");
        expect(level).toEqual(treeWithoutLeaves[0]);
      }
    })
  );
});

속성 2: 더 크고 더 큰 수준을 만들어야 합니다.

for any requested size of tree n
it should render a tree having levels being larger and larger as we move down in the tree

it("should create larger and larger levels", () => {
  fc.assert(
    fc.property(fc.integer({ min: 1, max: 1000 }), (n) => {
      // Arrange / Act
      const tree = drawTree(n);

      // Assert
      const treeLevels = tree.split("\n").map((level) => level.trim());
      for (let index = 1; index < n; ++index) {
        expect(treeLevels[index]).toContain(treeLevels[index - 1]);
      }
    })
  );
});

속성 3: 나뭇잎을 한 수준에서 다음 수준으로 오프셋해야 합니다.

for any requested size of tree n
it should render a tree with leaves being offset from one level to the next one

it("should offset leaves from one level to the next one", () => {
  fc.assert(
    fc.property(fc.integer({ min: 1, max: 1000 }), (n) => {
      // Arrange / Act
      const tree = drawTree(n);

      // Assert
      const treeLevels = tree.split("\n").map((level) => level.trim());
      for (let index = 1; index < n; ++index) {
        expect(treeLevels[index]).toEqual("(" + treeLevels[index - 1] + ")");
      }
    })
  );
});

속성 4: 상단과 동일한 수준으로 크기 2의 기반을 만들어야 합니다.

for any requested size of tree n
it should render a tree having a base of size 2

it("should create a base of size two with levels identical to the top", () => {
  fc.assert(
    fc.property(fc.integer({ min: 1, max: 1000 }), (n) => {
      // Arrange / Act
      const tree = drawTree(n);

      // Assert
      const treeLevels = tree.split("\n");
      expect(treeLevels).toHaveLength(n + 2);
      expect(treeLevels[n]).toEqual(treeLevels[0]);
      expect(treeLevels[n + 1]).toEqual(treeLevels[0]);
    })
  );
});