A poem made of lines from other poems is called a cento. That name might apply to these songs too. I tried to think of one and couldn't, so I'm impressed by the excellent ones people came up with!

I wonder if the following is Dorothy Scarborough's "original" version of "The Raggle-Taggle Gypsies." It's very similar to "The Gypsy Laddie" and "Gypsy Laddies" in the DT. I'm just entering it because it mentions Johnny Faa. (Also an early use of "wow.")

From The Harper Anthology of Poetry, edited by John Frederick Nims. He got it from A. Ramsey's The Tea-Table Miscellany, Vol. IV (1740).

THE GYPSY LADDIE

The gypsies came to our good lord's gate,
And wow but they sang sweetly!
They sang sae sweet and sae very compleat
That down came the fair lady.

And she came tripping down the stair,
And a' her maids before her;
As soon as they saw her well-far'd face,
They coost the glamer o'er her.

"Gae tak frae me this gay mantile,
And bring to me a plaidie;
For if kith and kin and a' had sworn,
I'll follow the gypsy laddie.

"Yestreen I lay in a well-made bed,
And my good lord beside me;
This night I'll ly in a tenant's barn,
Whatever shall betide me."

"Come to your bed," says Johnny Faa,
"Oh come to your bed, my deary;
For I vow and I swear, by the hilt of my sword,
That your lord shall nae mair come near ye."

"I'll go to bed to my Johnny Faa,
I'll go to bed to my deary;
For I vow and I swear, by what past yestreen,
That my lord shall nae mair come near me.

"I'll mak a hap to my Johnny Faa,
And I'll mak a hap to my deary;
And he's get a' the coat gaes round,
And my lord shall nae mair come near me."

And when our lord came hame at een,
And speir'd for his fair lady,
The tane she cry'd, and the other reply'd,
"She's away with the gypsy laddie."

Gae saddle to me the black, black steed,
Gae saddle and make him ready;
Before that I either eat or sleep,
I'll gae seek my fair lady."

And we were fifteen well-made men,
Although we were nae bonny;
And we were a' put down for ane,
A fair young wanton lady.

According to Nims's notes, "hap" means a covering such as a quilt or a coat, and "speired" means "asked".