// Step 1 is the removal of standard suffixes
//
func step1(word *snowballword.SnowballWord) bool {
suffix, suffixRunes := word.FirstSuffix(
"issements", "issement", "atrices", "utions", "usions", "logies",
"emment", "ements", "atrice", "ations", "ateurs", "amment", "ution",
"usion", "ments", "logie", "istes", "ismes", "iqUes", "euses",
"ences", "ement", "ation", "ateur", "ances", "ables", "ment",
"ités", "iste", "isme", "iqUe", "euse", "ence", "eaux", "ance",
"able", "ives", "ité", "eux", "aux", "ive", "ifs", "if",
)
if suffix == "" {
return false
}
isInR1 := (word.R1start <= len(word.RS)-len(suffixRunes))
isInR2 := (word.R2start <= len(word.RS)-len(suffixRunes))
isInRV := (word.RVstart <= len(word.RS)-len(suffixRunes))
// Handle simple replacements & deletions in R2 first
if isInR2 {
// Handle simple replacements in R2
repl := ""
switch suffix {
case "logie", "logies":
repl = "log"
case "usion", "ution", "usions", "utions":
repl = "u"
case "ence", "ences":
repl = "ent"
}
if repl != "" {
word.ReplaceSuffixRunes(suffixRunes, []rune(repl), true)
return true
}
// Handle simple deletions in R2
switch suffix {
case "ance", "iqUe", "isme", "able", "iste", "eux", "ances", "iqUes", "ismes", "ables", "istes":
word.RemoveLastNRunes(len(suffixRunes))
return true
}
}
// Handle simple replacements in RV
if isInRV {
// NOTE: these are "special" suffixes in that
// we must still do steps 2a and 2b of the
// French stemmer even when these suffixes are
// found in step1. Therefore, we are returning
// `false` here.
repl := ""
switch suffix {
case "amment":
repl = "ant"
case "emment":
repl = "ent"
}
if repl != "" {
word.ReplaceSuffixRunes(suffixRunes, []rune(repl), true)
return false
}
// Delete if preceded by a vowel that is also in RV
if suffix == "ment" || suffix == "ments" {
idx := len(word.RS) - len(suffixRunes) - 1
if idx >= word.RVstart && isLowerVowel(word.RS[idx]) {
word.RemoveLastNRunes(len(suffixRunes))
return false
}
return false
}
}
// Handle all the other "special" cases. All of these
// return true immediately after changing the word.
//
switch suffix {
case "eaux":
// Replace with eau
word.ReplaceSuffixRunes(suffixRunes, []rune("eau"), true)
return true
case "aux":
// Replace with al if in R1
if isInR1 {
word.ReplaceSuffixRunes(suffixRunes, []rune("al"), true)
return true
}
case "euse", "euses":
// Delete if in R2, else replace by eux if in R1
if isInR2 {
word.RemoveLastNRunes(len(suffixRunes))
return true
} else if isInR1 {
word.ReplaceSuffixRunes(suffixRunes, []rune("eux"), true)
return true
}
case "issement", "issements":
// Delete if in R1 and preceded by a non-vowel
if isInR1 {
idx := len(word.RS) - len(suffixRunes) - 1
if idx >= 0 && isLowerVowel(word.RS[idx]) == false {
word.RemoveLastNRunes(len(suffixRunes))
return true
}
}
return false
case "atrice", "ateur", "ation", "atrices", "ateurs", "ations":
// Delete if in R2
if isInR2 {
word.RemoveLastNRunes(len(suffixRunes))
// If preceded by "ic", delete if in R2, else replace by "iqU".
newSuffix, newSuffixRunes := word.FirstSuffix("ic")
if newSuffix != "" {
if word.FitsInR2(len(newSuffixRunes)) {
word.RemoveLastNRunes(len(newSuffixRunes))
} else {
word.ReplaceSuffixRunes(newSuffixRunes, []rune("iqU"), true)
}
}
return true
}
case "ement", "ements":
if isInRV {
// Delete if in RV
word.RemoveLastNRunes(len(suffixRunes))
// If preceded by "iv", delete if in R2
// (and if further preceded by "at", delete if in R2)
newSuffix, newSuffixRunes := word.RemoveFirstSuffixIfIn(word.R2start, "iv")
if newSuffix != "" {
word.RemoveFirstSuffixIfIn(word.R2start, "at")
return true
}
// If preceded by "eus", delete if in R2, else replace by "eux" if in R1
newSuffix, newSuffixRunes = word.FirstSuffix("eus")
if newSuffix != "" {
newSuffixLen := len(newSuffixRunes)
if word.FitsInR2(newSuffixLen) {
word.RemoveLastNRunes(newSuffixLen)
} else if word.FitsInR1(newSuffixLen) {
word.ReplaceSuffixRunes(newSuffixRunes, []rune("eux"), true)
}
return true
}
// If preceded by abl or iqU, delete if in R2, otherwise,
newSuffix, newSuffixRunes = word.FirstSuffix("abl", "iqU")
if newSuffix != "" {
newSuffixLen := len(newSuffixRunes)
if word.FitsInR2(newSuffixLen) {
word.RemoveLastNRunes(newSuffixLen)
}
return true
}
// If preceded by ièr or Ièr, replace by i if in RV
newSuffix, newSuffixRunes = word.FirstSuffix("ièr", "Ièr")
if newSuffix != "" {
if word.FitsInRV(len(newSuffixRunes)) {
word.ReplaceSuffixRunes(newSuffixRunes, []rune("i"), true)
}
return true
}
return true
}
case "ité", "ités":
if isInR2 {
// Delete if in R2
word.RemoveLastNRunes(len(suffixRunes))
// If preceded by "abil", delete if in R2, else replace by "abl"
newSuffix, newSuffixRunes := word.FirstSuffix("abil")
if newSuffix != "" {
newSuffixLen := len(newSuffixRunes)
if word.FitsInR2(newSuffixLen) {
word.RemoveLastNRunes(newSuffixLen)
} else {
word.ReplaceSuffixRunes(newSuffixRunes, []rune("abl"), true)
}
return true
}
// If preceded by "ic", delete if in R2, else replace by "iqU"
newSuffix, newSuffixRunes = word.FirstSuffix("ic")
if newSuffix != "" {
newSuffixLen := len(newSuffixRunes)
if word.FitsInR2(newSuffixLen) {
word.RemoveLastNRunes(newSuffixLen)
} else {
word.ReplaceSuffixRunes(newSuffixRunes, []rune("iqU"), true)
}
return true
}
// If preceded by "iv", delete if in R2
newSuffix, newSuffixRunes = word.RemoveFirstSuffixIfIn(word.R2start, "iv")
return true
}
case "if", "ive", "ifs", "ives":
if isInR2 {
// Delete if in R2
word.RemoveLastNRunes(len(suffixRunes))
// If preceded by at, delete if in R2
newSuffix, newSuffixRunes := word.RemoveFirstSuffixIfIn(word.R2start, "at")
if newSuffix != "" {
// And if further preceded by ic, delete if in R2, else replace by iqU
newSuffix, newSuffixRunes = word.FirstSuffix("ic")
if newSuffix != "" {
newSuffixLen := len(newSuffixRunes)
if word.FitsInR2(newSuffixLen) {
word.RemoveLastNRunes(newSuffixLen)
} else {
word.ReplaceSuffixRunes(newSuffixRunes, []rune("iqU"), true)
}
}
}
return true
}
}
return false
}