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authorLibravatar Vyr Cossont <VyrCossont@users.noreply.github.com>2024-03-06 09:05:45 -0800
committerLibravatar GitHub <noreply@github.com>2024-03-06 18:05:45 +0100
commitfc3741365c27f1d703e8a736af95b95ff811cc45 (patch)
tree929f1d5e20d1469d63a3dfe81d38d89f9a073c5a /vendor/github.com/shopspring/decimal/rounding.go
parent[chore/bugfix] Little DB fixes (#2726) (diff)
downloadgotosocial-fc3741365c27f1d703e8a736af95b95ff811cc45.tar.xz
[bugfix] Fix Swagger spec and add test script (#2698)
* Add Swagger spec test script * Fix Swagger spec errors not related to statuses with polls * Add API tests that post a status with a poll * Fix creating a status with a poll from form params * Fix Swagger spec errors related to statuses with polls (this is the last error) * Fix Swagger spec warnings not related to unused definitions * Suppress a duplicate list update params definition that was somehow causing wrong param names * Add Swagger test to CI - updates Drone config - vendorizes go-swagger - fixes a file extension issue that caused the test script to generate JSON instead of YAML with the vendorized version * Put `Sample: ` on its own line everywhere * Remove unused id param from emojiCategoriesGet * Add 5 more pairs of profile fields to account update API Swagger * Remove Swagger prefix from dummy fields It makes the generated code look weird * Manually annotate params for statusCreate operation * Fix all remaining Swagger spec warnings - Change some models into operation parameters - Ignore models that already correspond to manually documented operation parameters but can't be trivially changed (those with file fields) * Documented that creating a status with scheduled_at isn't implemented yet * sign drone.yml * Fix filter API Swagger errors * fixup! Fix filter API Swagger errors --------- Co-authored-by: tobi <tobi.smethurst@protonmail.com>
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+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Multiprecision decimal numbers.
+// For floating-point formatting only; not general purpose.
+// Only operations are assign and (binary) left/right shift.
+// Can do binary floating point in multiprecision decimal precisely
+// because 2 divides 10; cannot do decimal floating point
+// in multiprecision binary precisely.
+
+package decimal
+
+type floatInfo struct {
+ mantbits uint
+ expbits uint
+ bias int
+}
+
+var float32info = floatInfo{23, 8, -127}
+var float64info = floatInfo{52, 11, -1023}
+
+// roundShortest rounds d (= mant * 2^exp) to the shortest number of digits
+// that will let the original floating point value be precisely reconstructed.
+func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) {
+ // If mantissa is zero, the number is zero; stop now.
+ if mant == 0 {
+ d.nd = 0
+ return
+ }
+
+ // Compute upper and lower such that any decimal number
+ // between upper and lower (possibly inclusive)
+ // will round to the original floating point number.
+
+ // We may see at once that the number is already shortest.
+ //
+ // Suppose d is not denormal, so that 2^exp <= d < 10^dp.
+ // The closest shorter number is at least 10^(dp-nd) away.
+ // The lower/upper bounds computed below are at distance
+ // at most 2^(exp-mantbits).
+ //
+ // So the number is already shortest if 10^(dp-nd) > 2^(exp-mantbits),
+ // or equivalently log2(10)*(dp-nd) > exp-mantbits.
+ // It is true if 332/100*(dp-nd) >= exp-mantbits (log2(10) > 3.32).
+ minexp := flt.bias + 1 // minimum possible exponent
+ if exp > minexp && 332*(d.dp-d.nd) >= 100*(exp-int(flt.mantbits)) {
+ // The number is already shortest.
+ return
+ }
+
+ // d = mant << (exp - mantbits)
+ // Next highest floating point number is mant+1 << exp-mantbits.
+ // Our upper bound is halfway between, mant*2+1 << exp-mantbits-1.
+ upper := new(decimal)
+ upper.Assign(mant*2 + 1)
+ upper.Shift(exp - int(flt.mantbits) - 1)
+
+ // d = mant << (exp - mantbits)
+ // Next lowest floating point number is mant-1 << exp-mantbits,
+ // unless mant-1 drops the significant bit and exp is not the minimum exp,
+ // in which case the next lowest is mant*2-1 << exp-mantbits-1.
+ // Either way, call it mantlo << explo-mantbits.
+ // Our lower bound is halfway between, mantlo*2+1 << explo-mantbits-1.
+ var mantlo uint64
+ var explo int
+ if mant > 1<<flt.mantbits || exp == minexp {
+ mantlo = mant - 1
+ explo = exp
+ } else {
+ mantlo = mant*2 - 1
+ explo = exp - 1
+ }
+ lower := new(decimal)
+ lower.Assign(mantlo*2 + 1)
+ lower.Shift(explo - int(flt.mantbits) - 1)
+
+ // The upper and lower bounds are possible outputs only if
+ // the original mantissa is even, so that IEEE round-to-even
+ // would round to the original mantissa and not the neighbors.
+ inclusive := mant%2 == 0
+
+ // Now we can figure out the minimum number of digits required.
+ // Walk along until d has distinguished itself from upper and lower.
+ for i := 0; i < d.nd; i++ {
+ l := byte('0') // lower digit
+ if i < lower.nd {
+ l = lower.d[i]
+ }
+ m := d.d[i] // middle digit
+ u := byte('0') // upper digit
+ if i < upper.nd {
+ u = upper.d[i]
+ }
+
+ // Okay to round down (truncate) if lower has a different digit
+ // or if lower is inclusive and is exactly the result of rounding
+ // down (i.e., and we have reached the final digit of lower).
+ okdown := l != m || inclusive && i+1 == lower.nd
+
+ // Okay to round up if upper has a different digit and either upper
+ // is inclusive or upper is bigger than the result of rounding up.
+ okup := m != u && (inclusive || m+1 < u || i+1 < upper.nd)
+
+ // If it's okay to do either, then round to the nearest one.
+ // If it's okay to do only one, do it.
+ switch {
+ case okdown && okup:
+ d.Round(i + 1)
+ return
+ case okdown:
+ d.RoundDown(i + 1)
+ return
+ case okup:
+ d.RoundUp(i + 1)
+ return
+ }
+ }
+}