1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
|
package dotty.tools
package dotc
package typer
import ast.{tpd, untpd}
import ast.Trees._
import core._
import util.SimpleMap
import Symbols._, Names._, Denotations._, Types._, Contexts._, StdNames._, Flags._
import Decorators.StringInterpolators
object ImportInfo {
/** The import info for a root import from given symbol `sym` */
def rootImport(refFn: () => TermRef)(implicit ctx: Context) = {
val selectors = untpd.Ident(nme.WILDCARD) :: Nil
def expr = tpd.Ident(refFn())
def imp = tpd.Import(expr, selectors)
new ImportInfo(imp.symbol, selectors, isRootImport = true)
}
}
/** Info relating to an import clause
* @param sym The import symbol defined by the clause
* @param selectors The selector clauses
* @param rootImport true if this is one of the implicit imports of scala, java.lang
* or Predef in the start context, false otherwise.
*/
class ImportInfo(symf: => Symbol, val selectors: List[untpd.Tree], val isRootImport: Boolean = false)(implicit ctx: Context) {
lazy val sym = symf
/** The (TermRef) type of the qualifier of the import clause */
def site(implicit ctx: Context): Type = {
val ImportType(expr) = sym.info
expr.tpe
}
/** The names that are excluded from any wildcard import */
def excluded: Set[TermName] = { ensureInitialized(); myExcluded }
/** A mapping from renamed to original names */
def reverseMapping: SimpleMap[TermName, TermName] = { ensureInitialized(); myMapped }
/** The original names imported by-name before renaming */
def originals: Set[TermName] = { ensureInitialized(); myOriginals }
/** Does the import clause end with wildcard? */
def isWildcardImport = { ensureInitialized(); myWildcardImport }
private var myExcluded: Set[TermName] = null
private var myMapped: SimpleMap[TermName, TermName] = null
private var myOriginals: Set[TermName] = null
private var myWildcardImport: Boolean = false
/** Compute info relating to the selector list */
private def ensureInitialized(): Unit = if (myExcluded == null) {
myExcluded = Set()
myMapped = SimpleMap.Empty
myOriginals = Set()
def recur(sels: List[untpd.Tree]): Unit = sels match {
case sel :: sels1 =>
sel match {
case Thicket(Ident(name: TermName) :: Ident(nme.WILDCARD) :: Nil) =>
myExcluded += name
case Thicket(Ident(from: TermName) :: Ident(to: TermName) :: Nil) =>
myMapped = myMapped.updated(to, from)
myExcluded += from
myOriginals += from
case Ident(nme.WILDCARD) =>
myWildcardImport = true
case Ident(name: TermName) =>
myMapped = myMapped.updated(name, name)
myOriginals += name
}
recur(sels1)
case nil =>
}
recur(selectors)
}
/** The implicit references imported by this import clause */
def importedImplicits: List[TermRef] = {
val pre = site
if (isWildcardImport) {
val refs = pre.implicitMembers
if (excluded.isEmpty) refs
else refs filterNot (ref => excluded contains ref.name.toTermName)
} else
for {
renamed <- reverseMapping.keys
denot <- pre.member(reverseMapping(renamed)).altsWith(_ is Implicit)
} yield TermRef.withSigAndDenot(pre, renamed, denot.signature, denot)
}
/** The root import symbol hidden by this symbol, or NoSymbol if no such symbol is hidden.
* Note: this computation needs to work even for un-initialized import infos, and
* is not allowed to force initialization.
*/
lazy val hiddenRoot: Symbol = {
val sym = site.termSymbol
def hasMaskingSelector = selectors exists {
case Thicket(_ :: Ident(nme.WILDCARD) :: Nil) => true
case _ => false
}
if ((defn.RootImportTypes exists (_.symbol == sym)) && hasMaskingSelector) sym else NoSymbol
}
override def toString = {
val siteStr = site.show
val exprStr = if (siteStr endsWith ".type") siteStr dropRight 5 else siteStr
val selectorStr = selectors match {
case Ident(name) :: Nil => name.show
case _ => "{...}"
}
i"import $exprStr.$selectorStr"
}
}
|