node_modules

1 files changed, 391 insertions, 0 deletions

diff --git a/node_modules/concordance/lib/diff.js b/node_modules/concordance/lib/diff.js
new file mode 100644
index 000000000..16191143f
--- /dev/null
+++ b/node_modules/concordance/lib/diff.js
@@ -0,0 +1,391 @@
+'use strict'
+
+const constants = require('./constants')
+const describe = require('./describe')
+const lineBuilder = require('./lineBuilder')
+const recursorUtils = require('./recursorUtils')
+const shouldCompareDeep = require('./shouldCompareDeep')
+const symbolProperties = require('./symbolProperties')
+const themeUtils = require('./themeUtils')
+const Circular = require('./Circular')
+const Indenter = require('./Indenter')
+
+const AMBIGUOUS = constants.AMBIGUOUS
+const DEEP_EQUAL = constants.DEEP_EQUAL
+const UNEQUAL = constants.UNEQUAL
+const SHALLOW_EQUAL = constants.SHALLOW_EQUAL
+const NOOP = Symbol('NOOP')
+
+const alwaysFormat = () => true
+
+function compareComplexShape (lhs, rhs) {
+  let result = lhs.compare(rhs)
+  if (result === DEEP_EQUAL) return DEEP_EQUAL
+  if (result === UNEQUAL || !shouldCompareDeep(result, lhs, rhs)) return UNEQUAL
+
+  let collectedSymbolProperties = false
+  let lhsRecursor = lhs.createRecursor()
+  let rhsRecursor = rhs.createRecursor()
+
+  do {
+    lhs = lhsRecursor()
+    rhs = rhsRecursor()
+
+    if (lhs === null && rhs === null) return SHALLOW_EQUAL
+    if (lhs === null || rhs === null) return UNEQUAL
+
+    result = lhs.compare(rhs)
+    if (result === UNEQUAL) return UNEQUAL
+    if (
+      result === AMBIGUOUS &&
+      lhs.isProperty === true && !collectedSymbolProperties &&
+      shouldCompareDeep(result, lhs, rhs)
+    ) {
+      collectedSymbolProperties = true
+      const lhsCollector = new symbolProperties.Collector(lhs, lhsRecursor)
+      const rhsCollector = new symbolProperties.Collector(rhs, rhsRecursor)
+
+      lhsRecursor = recursorUtils.sequence(
+        lhsCollector.createRecursor(),
+        recursorUtils.unshift(lhsRecursor, lhsCollector.collectAll()))
+      rhsRecursor = recursorUtils.sequence(
+        rhsCollector.createRecursor(),
+        recursorUtils.unshift(rhsRecursor, rhsCollector.collectAll()))
+    }
+  } while (true)
+}
+
+function diffDescriptors (lhs, rhs, options) {
+  const theme = themeUtils.normalize(options)
+  const invert = options ? options.invert === true : false
+
+  const lhsCircular = new Circular()
+  const rhsCircular = new Circular()
+  const maxDepth = (options && options.maxDepth) || 0
+
+  let indent = new Indenter(0, '  ')
+
+  const lhsStack = []
+  const rhsStack = []
+  let topIndex = -1
+
+  const buffer = lineBuilder.buffer()
+  const diffStack = []
+  let diffIndex = -1
+
+  const isCircular = descriptor => lhsCircular.has(descriptor) || rhsCircular.has(descriptor)
+
+  const format = (builder, subject, circular) => {
+    if (diffIndex >= 0 && !diffStack[diffIndex].shouldFormat(subject)) return
+
+    if (circular.has(subject)) {
+      diffStack[diffIndex].formatter.append(builder.single(theme.circular))
+      return
+    }
+
+    const formatStack = []
+    let formatIndex = -1
+
+    do {
+      if (circular.has(subject)) {
+        formatStack[formatIndex].formatter.append(builder.single(theme.circular), subject)
+      } else {
+        let didFormat = false
+        if (typeof subject.formatDeep === 'function') {
+          let formatted = subject.formatDeep(themeUtils.applyModifiers(subject, theme), indent)
+          if (formatted !== null) {
+            didFormat = true
+
+            if (formatIndex === -1) {
+              formatted = builder.setDefaultGutter(formatted)
+              if (diffIndex === -1) {
+                buffer.append(formatted)
+              } else {
+                diffStack[diffIndex].formatter.append(formatted, subject)
+              }
+            } else {
+              formatStack[formatIndex].formatter.append(formatted, subject)
+            }
+          }
+        }
+
+        if (!didFormat && typeof subject.formatShallow === 'function') {
+          const formatter = subject.formatShallow(themeUtils.applyModifiers(subject, theme), indent)
+          const recursor = subject.createRecursor()
+
+          if (formatter.increaseIndent && maxDepth > 0 && indent.level === maxDepth) {
+            const isEmpty = recursor() === null
+            let formatted = !isEmpty && typeof formatter.maxDepth === 'function'
+              ? formatter.maxDepth()
+              : formatter.finalize()
+
+            if (formatIndex === -1) {
+              formatted = builder.setDefaultGutter(formatted)
+              diffStack[diffIndex].formatter.append(formatted, subject)
+            } else {
+              formatStack[formatIndex].formatter.append(formatted, subject)
+            }
+          } else {
+            formatStack.push({
+              formatter,
+              recursor,
+              decreaseIndent: formatter.increaseIndent,
+              shouldFormat: formatter.shouldFormat || alwaysFormat,
+              subject
+            })
+            formatIndex++
+
+            if (formatter.increaseIndent) indent = indent.increase()
+            circular.add(subject)
+          }
+        }
+      }
+
+      while (formatIndex >= 0) {
+        do {
+          subject = formatStack[formatIndex].recursor()
+        } while (subject && !formatStack[formatIndex].shouldFormat(subject))
+
+        if (subject) {
+          break
+        }
+
+        const record = formatStack.pop()
+        formatIndex--
+        if (record.decreaseIndent) indent = indent.decrease()
+        circular.delete(record.subject)
+
+        let formatted = record.formatter.finalize()
+        if (formatIndex === -1) {
+          formatted = builder.setDefaultGutter(formatted)
+          if (diffIndex === -1) {
+            buffer.append(formatted)
+          } else {
+            diffStack[diffIndex].formatter.append(formatted, record.subject)
+          }
+        } else {
+          formatStack[formatIndex].formatter.append(formatted, record.subject)
+        }
+      }
+    } while (formatIndex >= 0)
+  }
+
+  do {
+    let compareResult = NOOP
+    if (lhsCircular.has(lhs)) {
+      compareResult = lhsCircular.get(lhs) === rhsCircular.get(rhs)
+        ? DEEP_EQUAL
+        : UNEQUAL
+    } else if (rhsCircular.has(rhs)) {
+      compareResult = UNEQUAL
+    }
+
+    let firstPassSymbolProperty = false
+    if (lhs.isProperty === true) {
+      compareResult = lhs.compare(rhs)
+      if (compareResult === AMBIGUOUS) {
+        const parent = lhsStack[topIndex].subject
+        firstPassSymbolProperty = parent.isSymbolPropertiesCollector !== true && parent.isSymbolPropertiesComparable !== true
+      }
+    }
+
+    let didFormat = false
+    let mustRecurse = false
+    if (compareResult !== DEEP_EQUAL && !firstPassSymbolProperty && typeof lhs.prepareDiff === 'function') {
+      const lhsRecursor = topIndex === -1 ? null : lhsStack[topIndex].recursor
+      const rhsRecursor = topIndex === -1 ? null : rhsStack[topIndex].recursor
+
+      const instructions = lhs.prepareDiff(
+        rhs,
+        lhsRecursor,
+        rhsRecursor,
+        compareComplexShape,
+        isCircular)
+
+      if (instructions !== null) {
+        if (topIndex >= 0) {
+          if (typeof instructions.lhsRecursor === 'function') {
+            lhsStack[topIndex].recursor = instructions.lhsRecursor
+          }
+          if (typeof instructions.rhsRecursor === 'function') {
+            rhsStack[topIndex].recursor = instructions.rhsRecursor
+          }
+        }
+
+        if (instructions.compareResult) {
+          compareResult = instructions.compareResult
+        }
+        if (instructions.mustRecurse === true) {
+          mustRecurse = true
+        } else {
+          if (instructions.actualIsExtraneous === true) {
+            format(lineBuilder.actual, lhs, lhsCircular)
+            didFormat = true
+          } else if (instructions.multipleAreExtraneous === true) {
+            for (const extraneous of instructions.descriptors) {
+              format(lineBuilder.actual, extraneous, lhsCircular)
+            }
+            didFormat = true
+          } else if (instructions.expectedIsMissing === true) {
+            format(lineBuilder.expected, rhs, rhsCircular)
+            didFormat = true
+          } else if (instructions.multipleAreMissing === true) {
+            for (const missing of instructions.descriptors) {
+              format(lineBuilder.expected, missing, rhsCircular)
+            }
+            didFormat = true
+          } else if (instructions.isUnequal === true) {
+            format(lineBuilder.actual, lhs, lhsCircular)
+            format(lineBuilder.expected, rhs, rhsCircular)
+            didFormat = true
+          } else if (!instructions.compareResult) {
+            // TODO: Throw a useful, custom error
+            throw new Error('Illegal result of prepareDiff()')
+          }
+        }
+      }
+    }
+
+    if (!didFormat) {
+      if (compareResult === NOOP) {
+        compareResult = lhs.compare(rhs)
+      }
+
+      if (!mustRecurse) {
+        mustRecurse = shouldCompareDeep(compareResult, lhs, rhs)
+      }
+
+      if (compareResult === DEEP_EQUAL) {
+        format(lineBuilder, lhs, lhsCircular)
+      } else if (mustRecurse) {
+        if (compareResult === AMBIGUOUS && lhs.isProperty === true) {
+          // Replace both sides by a pseudo-descriptor which collects symbol
+          // properties instead.
+          lhs = new symbolProperties.Collector(lhs, lhsStack[topIndex].recursor)
+          rhs = new symbolProperties.Collector(rhs, rhsStack[topIndex].recursor)
+          // Replace the current recursors so they can continue correctly after
+          // the collectors have been "compared". This is necessary since the
+          // collectors eat the first value after the last symbol property.
+          lhsStack[topIndex].recursor = recursorUtils.unshift(lhsStack[topIndex].recursor, lhs.collectAll())
+          rhsStack[topIndex].recursor = recursorUtils.unshift(rhsStack[topIndex].recursor, rhs.collectAll())
+        }
+
+        if (typeof lhs.diffShallow === 'function') {
+          const formatter = lhs.diffShallow(rhs, themeUtils.applyModifiers(lhs, theme), indent)
+          diffStack.push({
+            formatter,
+            origin: lhs,
+            decreaseIndent: formatter.increaseIndent,
+            exceedsMaxDepth: formatter.increaseIndent && maxDepth > 0 && indent.level >= maxDepth,
+            shouldFormat: formatter.shouldFormat || alwaysFormat
+          })
+          diffIndex++
+
+          if (formatter.increaseIndent) indent = indent.increase()
+        } else if (typeof lhs.formatShallow === 'function') {
+          const formatter = lhs.formatShallow(themeUtils.applyModifiers(lhs, theme), indent)
+          diffStack.push({
+            formatter,
+            decreaseIndent: formatter.increaseIndent,
+            exceedsMaxDepth: formatter.increaseIndent && maxDepth > 0 && indent.level >= maxDepth,
+            shouldFormat: formatter.shouldFormat || alwaysFormat,
+            subject: lhs
+          })
+          diffIndex++
+
+          if (formatter.increaseIndent) indent = indent.increase()
+        }
+
+        lhsCircular.add(lhs)
+        rhsCircular.add(rhs)
+
+        lhsStack.push({ diffIndex, subject: lhs, recursor: lhs.createRecursor() })
+        rhsStack.push({ diffIndex, subject: rhs, recursor: rhs.createRecursor() })
+        topIndex++
+      } else {
+        const diffed = typeof lhs.diffDeep === 'function'
+          ? lhs.diffDeep(rhs, themeUtils.applyModifiers(lhs, theme), indent)
+          : null
+
+        if (diffed === null) {
+          format(lineBuilder.actual, lhs, lhsCircular)
+          format(lineBuilder.expected, rhs, rhsCircular)
+        } else {
+          if (diffIndex === -1) {
+            buffer.append(diffed)
+          } else {
+            diffStack[diffIndex].formatter.append(diffed, lhs)
+          }
+        }
+      }
+    }
+
+    while (topIndex >= 0) {
+      lhs = lhsStack[topIndex].recursor()
+      rhs = rhsStack[topIndex].recursor()
+
+      if (lhs !== null && rhs !== null) {
+        break
+      }
+
+      if (lhs === null && rhs === null) {
+        const lhsRecord = lhsStack.pop()
+        const rhsRecord = rhsStack.pop()
+        lhsCircular.delete(lhsRecord.subject)
+        rhsCircular.delete(rhsRecord.subject)
+        topIndex--
+
+        if (lhsRecord.diffIndex === diffIndex) {
+          const record = diffStack.pop()
+          diffIndex--
+          if (record.decreaseIndent) indent = indent.decrease()
+
+          let formatted = record.formatter.finalize()
+          if (record.exceedsMaxDepth && !formatted.hasGutter) {
+            // The record exceeds the max depth, but contains no actual diff.
+            // Discard the potentially deep formatting and format just the
+            // original subject.
+            const subject = lhsRecord.subject
+            const formatter = subject.formatShallow(themeUtils.applyModifiers(subject, theme), indent)
+            const isEmpty = subject.createRecursor()() === null
+            formatted = !isEmpty && typeof formatter.maxDepth === 'function'
+              ? formatter.maxDepth()
+              : formatter.finalize()
+          }
+
+          if (diffIndex === -1) {
+            buffer.append(formatted)
+          } else {
+            diffStack[diffIndex].formatter.append(formatted, record.subject)
+          }
+        }
+      } else {
+        let builder, circular, stack, subject
+        if (lhs === null) {
+          builder = lineBuilder.expected
+          circular = rhsCircular
+          stack = rhsStack
+          subject = rhs
+        } else {
+          builder = lineBuilder.actual
+          circular = lhsCircular
+          stack = lhsStack
+          subject = lhs
+        }
+
+        do {
+          format(builder, subject, circular)
+          subject = stack[topIndex].recursor()
+        } while (subject !== null)
+      }
+    }
+  } while (topIndex >= 0)
+
+  return buffer.toString({diff: true, invert, theme})
+}
+exports.diffDescriptors = diffDescriptors
+
+function diff (actual, expected, options) {
+  return diffDescriptors(describe(actual, options), describe(expected, options), options)
+}
+exports.diff = diff