Add node modules and new code for release (#39)

Co-authored-by: tbarnes94 <tbarnes94@users.noreply.github.com>

node_modules/v8-to-istanbul/lib/source.js

@@ -0,0 +1,199 @@
+const CovLine = require('./line')
+const { GREATEST_LOWER_BOUND, LEAST_UPPER_BOUND } = require('source-map').SourceMapConsumer
+
+module.exports = class CovSource {
+  constructor (sourceRaw, wrapperLength) {
+    sourceRaw = sourceRaw.trimEnd()
+    this.lines = []
+    this.eof = sourceRaw.length
+    this.shebangLength = getShebangLength(sourceRaw)
+    this.wrapperLength = wrapperLength - this.shebangLength
+    this._buildLines(sourceRaw)
+  }
+
+  _buildLines (source) {
+    let position = 0
+    let ignoreCount = 0
+    for (const [i, lineStr] of source.split(/(?<=\r?\n)/u).entries()) {
+      const line = new CovLine(i + 1, position, lineStr)
+      if (ignoreCount > 0) {
+        line.ignore = true
+        ignoreCount--
+      } else {
+        ignoreCount = this._parseIgnoreNext(lineStr, line)
+      }
+      this.lines.push(line)
+      position += lineStr.length
+    }
+  }
+
+  _parseIgnoreNext (lineStr, line) {
+    const testIgnoreNextLines = lineStr.match(/^\W*\/\* c8 ignore next (?<count>[0-9]+)? *\*\/\W*$/)
+    if (testIgnoreNextLines) {
+      line.ignore = true
+      if (testIgnoreNextLines.groups.count) {
+        return Number(testIgnoreNextLines.groups.count)
+      } else {
+        return 1
+      }
+    } else {
+      if (lineStr.match(/\/\* c8 ignore next \*\//)) {
+        line.ignore = true
+      }
+    }
+
+    return 0
+  }
+
+  // given a start column and end column in absolute offsets within
+  // a source file (0 - EOF), returns the relative line column positions.
+  offsetToOriginalRelative (sourceMap, startCol, endCol) {
+    const lines = this.lines.filter((line, i) => {
+      return startCol <= line.endCol && endCol >= line.startCol
+    })
+    if (!lines.length) return {}
+
+    const start = originalPositionTryBoth(
+      sourceMap,
+      lines[0].line,
+      Math.max(0, startCol - lines[0].startCol)
+    )
+    let end = originalEndPositionFor(
+      sourceMap,
+      lines[lines.length - 1].line,
+      endCol - lines[lines.length - 1].startCol
+    )
+
+    if (!(start && end)) {
+      return {}
+    }
+
+    if (!(start.source && end.source)) {
+      return {}
+    }
+
+    if (start.source !== end.source) {
+      return {}
+    }
+
+    if (start.line === end.line && start.column === end.column) {
+      end = sourceMap.originalPositionFor({
+        line: lines[lines.length - 1].line,
+        column: endCol - lines[lines.length - 1].startCol,
+        bias: LEAST_UPPER_BOUND
+      })
+      end.column -= 1
+    }
+
+    return {
+      source: start.source,
+      startLine: start.line,
+      relStartCol: start.column,
+      endLine: end.line,
+      relEndCol: end.column
+    }
+  }
+
+  relativeToOffset (line, relCol) {
+    line = Math.max(line, 1)
+    if (this.lines[line - 1] === undefined) return this.eof
+    return Math.min(this.lines[line - 1].startCol + relCol, this.lines[line - 1].endCol)
+  }
+}
+
+// this implementation is pulled over from istanbul-lib-sourcemap:
+// https://github.com/istanbuljs/istanbuljs/blob/master/packages/istanbul-lib-source-maps/lib/get-mapping.js
+//
+/**
+ * AST ranges are inclusive for start positions and exclusive for end positions.
+ * Source maps are also logically ranges over text, though interacting with
+ * them is generally achieved by working with explicit positions.
+ *
+ * When finding the _end_ location of an AST item, the range behavior is
+ * important because what we're asking for is the _end_ of whatever range
+ * corresponds to the end location we seek.
+ *
+ * This boils down to the following steps, conceptually, though the source-map
+ * library doesn't expose primitives to do this nicely:
+ *
+ * 1. Find the range on the generated file that ends at, or exclusively
+ *    contains the end position of the AST node.
+ * 2. Find the range on the original file that corresponds to
+ *    that generated range.
+ * 3. Find the _end_ location of that original range.
+ */
+function originalEndPositionFor (sourceMap, line, column) {
+  // Given the generated location, find the original location of the mapping
+  // that corresponds to a range on the generated file that overlaps the
+  // generated file end location. Note however that this position on its
+  // own is not useful because it is the position of the _start_ of the range
+  // on the original file, and we want the _end_ of the range.
+  const beforeEndMapping = originalPositionTryBoth(
+    sourceMap,
+    line,
+    Math.max(column - 1, 1)
+  )
+
+  if (beforeEndMapping.source === null) {
+    return null
+  }
+
+  // Convert that original position back to a generated one, with a bump
+  // to the right, and a rightward bias. Since 'generatedPositionFor' searches
+  // for mappings in the original-order sorted list, this will find the
+  // mapping that corresponds to the one immediately after the
+  // beforeEndMapping mapping.
+  const afterEndMapping = sourceMap.generatedPositionFor({
+    source: beforeEndMapping.source,
+    line: beforeEndMapping.line,
+    column: beforeEndMapping.column + 1,
+    bias: LEAST_UPPER_BOUND
+  })
+  if (
+  // If this is null, it means that we've hit the end of the file,
+  // so we can use Infinity as the end column.
+    afterEndMapping.line === null ||
+      // If these don't match, it means that the call to
+      // 'generatedPositionFor' didn't find any other original mappings on
+      // the line we gave, so consider the binding to extend to infinity.
+      sourceMap.originalPositionFor(afterEndMapping).line !==
+          beforeEndMapping.line
+  ) {
+    return {
+      source: beforeEndMapping.source,
+      line: beforeEndMapping.line,
+      column: Infinity
+    }
+  }
+
+  // Convert the end mapping into the real original position.
+  return sourceMap.originalPositionFor(afterEndMapping)
+}
+
+function originalPositionTryBoth (sourceMap, line, column) {
+  const original = sourceMap.originalPositionFor({
+    line,
+    column,
+    bias: GREATEST_LOWER_BOUND
+  })
+  if (original.line === null) {
+    return sourceMap.originalPositionFor({
+      line,
+      column,
+      bias: LEAST_UPPER_BOUND
+    })
+  } else {
+    return original
+  }
+}
+
+function getShebangLength (source) {
+  if (source.indexOf('#!') === 0) {
+    const match = source.match(/(?<shebang>#!.*)/)
+    if (match) {
+      return match.groups.shebang.length
+    }
+  } else {
+    return 0
+  }
+}