Majuma ni nini katika kupima?

Question

Accepted Answer

**Majuma** ni kauli katika mtihani inayochekeza kama hali fulani ni kweli — kuthibitisha kwamba matokeo halisi yanafanana na matokeo yanayotaka. Ni kiini cha jinsi mitihani inavyoamua kupita au kushindwa: ikiwa majuma yafeli, mtihani unafeli.

## Majuma yanayofanya nini

```text
An ASSERTION checks that something is as expected:
  → "assert that the actual value EQUALS the expected value"
  → if TRUE → the assertion passes; if FALSE → the assertion FAILS → the TEST FAILS
→ Assertions are how a test VERIFIES behavior (the "check" part of a test).
```

## Aina za majuma yanayojulikana

```js
// equality
expect(result).toBe(5);                  // strict equality
expect(obj).toEqual({ name: 'Ann' });    // deep/value equality (objects)

// truthiness / null
expect(value).toBeTruthy();
expect(value).toBeNull();
expect(value).toBeDefined();

// comparisons
expect(count).toBeGreaterThan(0);
expect(price).toBeLessThanOrEqual(100);

// collections / strings
expect(array).toContain('item');
expect(array).toHaveLength(3);
expect(text).toMatch(/pattern/);          // regex

// errors
expect(() => risky()).toThrow();          // expect a function to throw

// negation
expect(value).not.toBe(null);
```

## Majuma mazuri

```text
✓ Assert the SPECIFIC expected outcome (clear what's being checked)
✓ Use the RIGHT matcher (toBe vs toEqual; specific > generic)
✓ Clear FAILURE messages (good assertions/matchers explain what failed)
✓ Don't over-assert (test one behavior) or under-assert (verify the actual result)
```

## Kwa nini inakusudiwa

Kuelewa majuma ni jambo la msingi kwa sababu ni **utaratibu wa core ambao mitihani inathibitisha tabia** — kuamua kupita au kushindwa — kwa hiyo ni muhimu, ujuzi wa lazima kwa kuandika mtihani mwingine.

Majuma **yachekeza kwamba hali fulani ni kweli** (kawaida kwamba matokeo halisi yanafanana na matokeo yanayotaka), na ni sehemu ya "uthibitisho" wa mtihani: ikiwa majuma yapita cheki inafanya kazi, na ikiwa yafeli mtihani unafeli.

Bila majuma, mtihani haitathibitishi kitu chochote — kwa hiyo kuielewa ni jambo la msingi la kuandika mitihani inayomaanisha.

Kuelewa **aina za majuma yanayojulikana** — kufanana (kibinafsi `toBe` dhidi ya kina/thamani `toEqual` kwa vitu, tofauti muhimu), maangalizo ya ukweli na cheki za null, ulinganisho, cheki za mkusanyo na kamba, majuma ya hitilafu (kuthibitisha chaguo la kukokotoa linakosea), na kufanya upingaji — ni ujuzi wa vitendo unaohitajika kwa kueleza matokeo ambayo mtihani unafaa kuthibitisha.

Kuelewa **mazoezi mazuri ya majuma** — kuthibitisha matokeo mahususi yanayotaka (safu wazi kuhusu kile kinachochekwa), kutumia kilinganishi sahihi (mfano `toEqual` kwa ulinganisho wa vitu, si `toBe`), kuhakikisha ujumbe wa kushindwa unaocezwa (ili mtihani unafeli unasaliti kile kilicho kibaya), na kusawazisha majuma (kupima tabia moja, lakini kuthibitisha matokeo halisi) — inaonyesha kuandika mitihani inayoelewa, inayofanya kazi.

Kwa sababu majuma ni jinsi kila mtihani unavyothibitisha tabia (cheki ya msingi inayofanya mtihani kumaanisha) na kuelewa wao — aina, kilinganishi sahihi, na mazoezi mazuri — ni muhimu kuandika mtihani mwingine unayothibitisha kitu, kuelewa majuma ni ujuzi wa msingi wa kupima — kizuizi cha core cha mitihani, muhimu kwa kueleza na kuthibitisha tabia iliyotaka, na jambo la msingi la kuandika mitihani inayochekeza usahihi kwa maana, ujuza wa msingi kwa mtu yeyote anayeandika mitihani.