"test double" meaning in English

{
  "forms": [
    {
      "form": "test doubles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "test double (plural test doubles)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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      "categories": [
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          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
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          "name": "Terms with Finnish translations",
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          "source": "w"
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          "name": "Terms with Mandarin translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Programming",
          "orig": "en:Programming",
          "parents": [
            "Computing",
            "Software engineering",
            "Technology",
            "Computer science",
            "Engineering",
            "Software",
            "All topics",
            "Sciences",
            "Applied sciences",
            "Media",
            "Fundamental",
            "Communication"
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          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2010, Ken Pugh, Lean-Agile Acceptance Test-Driven-Development, Pearson Education, →ISBN:",
          "text": "A test double is something that stands in for a real system when tests are being run. It comes from the idea of a double who stands in for the real actor when shooting a movie.",
          "type": "quote"
        }
      ],
      "glosses": [
        "An object or procedure that looks and behaves like its release-intended counterpart, but is actually a simplified version to reduce complexity and facilitate testing."
      ],
      "hyponyms": [
        {
          "word": "dummy"
        },
        {
          "word": "fake"
        },
        {
          "word": "mock object"
        },
        {
          "word": "mock"
        },
        {
          "word": "spy"
        },
        {
          "word": "stub"
        }
      ],
      "id": "en-test_double-en-noun-qdJBg8Hc",
      "links": [
        [
          "programming",
          "programming#Noun"
        ],
        [
          "object",
          "object"
        ],
        [
          "procedure",
          "procedure"
        ]
      ],
      "raw_glosses": [
        "(programming) An object or procedure that looks and behaves like its release-intended counterpart, but is actually a simplified version to reduce complexity and facilitate testing."
      ],
      "topics": [
        "computing",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "programming",
        "sciences"
      ],
      "translations": [
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "cèshì tìshēn",
          "sense": "object",
          "word": "測試替身 /测试替身"
        },
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "object",
          "word": "testisijainen"
        },
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "object",
          "word": "testijäljitelmä"
        }
      ],
      "wikipedia": [
        "test double"
      ]
    }
  ],
  "word": "test double"
}

{
  "forms": [
    {
      "form": "test doubles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "test double (plural test doubles)",
      "name": "en-noun"
    }
  ],
  "hyponyms": [
    {
      "word": "dummy"
    },
    {
      "word": "fake"
    },
    {
      "word": "mock object"
    },
    {
      "word": "mock"
    },
    {
      "word": "spy"
    },
    {
      "word": "stub"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "Terms with Mandarin translations",
        "en:Programming"
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      "examples": [
        {
          "ref": "2010, Ken Pugh, Lean-Agile Acceptance Test-Driven-Development, Pearson Education, →ISBN:",
          "text": "A test double is something that stands in for a real system when tests are being run. It comes from the idea of a double who stands in for the real actor when shooting a movie.",
          "type": "quote"
        }
      ],
      "glosses": [
        "An object or procedure that looks and behaves like its release-intended counterpart, but is actually a simplified version to reduce complexity and facilitate testing."
      ],
      "links": [
        [
          "programming",
          "programming#Noun"
        ],
        [
          "object",
          "object"
        ],
        [
          "procedure",
          "procedure"
        ]
      ],
      "raw_glosses": [
        "(programming) An object or procedure that looks and behaves like its release-intended counterpart, but is actually a simplified version to reduce complexity and facilitate testing."
      ],
      "topics": [
        "computing",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "programming",
        "sciences"
      ],
      "wikipedia": [
        "test double"
      ]
    }
  ],
  "translations": [
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "cèshì tìshēn",
      "sense": "object",
      "word": "測試替身 /测试替身"
    },
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "object",
      "word": "testisijainen"
    },
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "object",
      "word": "testijäljitelmä"
    }
  ],
  "word": "test double"
}