done, should be good to go

TODO

@@ -1,5 +1,9 @@
 - whitespace (specifically, ' ')
 
+- "quick-format" options - json-safe/escaped, mysql-safe/escaped, etc.
+
+- pretter printing for errors in main?
+
 - "Human Readability"?
 
 - Hash/Salted hash generator

pwgenerator/errs.go

@@ -6,6 +6,7 @@ import (
 
 var (
 	ErrBadType               error = errors.New("cannot typeswitch; unsupported type")
+	ErrEmptyCharsets         error = errors.New("empty character set/no character sets selected")
 	ErrIncompatCharsetFilter error = errors.New("the selected minimum requirements are not possible with selected/enabled charsets")
 	ErrSwitchedLenLimits     error = errors.New("the max password length is shorter than the minimum password length")
 	ErrTooSmall              error = errors.New("password max length too short for specified required chars")

pwgenerator/funcs_genopts.go

@@ -10,7 +10,7 @@ import (
 func (o *GenOpts) Generate() (passwords []string, err error) {
 
 	var passwds []string = make([]string, o.Count)
-	var charset CharSet = o.Chars()
+	var charset CharSet
 	var errs *multierr.MultiError = multierr.NewMultiError(nil)
 
 	if o.Count == 0 {
@@ -20,6 +20,14 @@ func (o *GenOpts) Generate() (passwords []string, err error) {
 		o.LengthMax = DefMaxLen
 	}
 
+	if err = o.sanChk(); err != nil {
+		return
+	}
+
+	if charset, err = o.Chars(); err != nil {
+		return
+	}
+
 	for idx, _ := range passwds {
 		if passwds[idx], err = o.generatePassword(charset); err != nil {
 			errs.AddError(err)
@@ -39,7 +47,6 @@ func (o *GenOpts) Generate() (passwords []string, err error) {
 // generatePassword generates a single password from CharSet c (plus any minimum requirements).
 func (o *GenOpts) generatePassword(c CharSet) (password string, err error) {
 
-	var maxMin uint
 	var trueMinLen uint
 	var passLenGap uint
 	var passLen int
@@ -47,36 +54,7 @@ func (o *GenOpts) generatePassword(c CharSet) (password string, err error) {
 	var filter *selectFilter = o.getFilter()
 	var isDisabled bool
 
-	// Sanity checks/error conditions.
+	if err = o.sanChk(); err != nil {
-	if o.explicitCharset != nil && len(o.explicitCharset) != 0 {
-		if o.CountUpper > 0 && !o.Alpha {
-			err = ErrIncompatCharsetFilter
-			return
-		}
-		if o.CountLower > 0 && !o.Alpha {
-			err = ErrIncompatCharsetFilter
-			return
-		}
-		if o.CountNumbers > 0 && !o.Numeric {
-			err = ErrIncompatCharsetFilter
-			return
-		}
-		if o.CountSymbols > 0 && !o.Symbols {
-			err = ErrIncompatCharsetFilter
-			return
-		}
-		if o.CountExtended > 0 && !o.ExtendedSymbols {
-			err = ErrIncompatCharsetFilter
-			return
-		}
-	}
-	maxMin = o.CountUpper + o.CountLower + o.CountNumbers + o.CountSymbols + o.CountExtended
-	if maxMin > o.LengthMax {
-		err = ErrTooSmall
-		return
-	}
-	if o.LengthMin > o.LengthMax {
-		err = ErrSwitchedLenLimits
 		return
 	}
 
@@ -204,10 +182,14 @@ func (o *GenOpts) generatePassword(c CharSet) (password string, err error) {
 }
 
 // Chars returns the list of evaluated characters that would be used in a GenOpts.
-func (o *GenOpts) Chars() (chars CharSet) {
+func (o *GenOpts) Chars() (chars CharSet, err error) {
 
 	chars = make(CharSet, 0)
 
+	if err = o.sanChk(); err != nil {
+		return
+	}
+
 	if o.explicitCharset != nil && len(o.explicitCharset) != 0 {
 		chars = o.explicitCharset
 		return
@@ -226,7 +208,10 @@ func (o *GenOpts) Chars() (chars CharSet) {
 		chars = append(chars, extendedSymbols...)
 	}
 
-	// TODO: Count* fields
+	if chars == nil || len(chars) == 0 {
+		err = ErrEmptyCharsets
+		return
+	}
 
 	return
 }
@@ -304,3 +289,43 @@ func (o *GenOpts) getFilter() (f *selectFilter) {
 
 	return
 }
+
+func (o *GenOpts) sanChk() (err error) {
+
+	var maxMin uint
+
+	// Sanity checks/error conditions.
+	if o.explicitCharset != nil && len(o.explicitCharset) != 0 {
+		if o.CountUpper > 0 && !o.Alpha {
+			err = ErrIncompatCharsetFilter
+			return
+		}
+		if o.CountLower > 0 && !o.Alpha {
+			err = ErrIncompatCharsetFilter
+			return
+		}
+		if o.CountNumbers > 0 && !o.Numeric {
+			err = ErrIncompatCharsetFilter
+			return
+		}
+		if o.CountSymbols > 0 && !o.Symbols {
+			err = ErrIncompatCharsetFilter
+			return
+		}
+		if o.CountExtended > 0 && !o.ExtendedSymbols {
+			err = ErrIncompatCharsetFilter
+			return
+		}
+	}
+	maxMin = o.CountUpper + o.CountLower + o.CountNumbers + o.CountSymbols + o.CountExtended
+	if maxMin > o.LengthMax {
+		err = ErrTooSmall
+		return
+	}
+	if o.LengthMin > o.LengthMax {
+		err = ErrSwitchedLenLimits
+		return
+	}
+
+	return
+}